Caesarea Maritima



Country: Israel

Locality: Caesarea

Coordinates (UTM; longitude/latitude): Long. 34° 53.5‘ E

Lat. 32° 30.5‘ N


Harbour location

Caesarea is located on a straight sandy coast, stretching from Atlit (23 km N) to Givat Olga (6 km S), and south of Haifa (40 km). To the north of Caesarea is the Crocodile River (Crocodilus; c.2 km) and to the south is the Alexander River (c.3 km). The main sources of information about Caesarea and its harbor construction come from the writings of Josephus. He gives a general geographical description of the site where king Herod chose to built the harbor, on a straight shoreline without any natural protection :


Research History

The earliest investigations of the ancient harbor of Sebastos were made in 1959 when Edwin Link and his wife Marion came to Israel to explore the port of Caesarea Maritima. The underwater remains of the submerged breakwaters may be seen from air in clear days and calm sea. At the terminus of one of the breakwaters, Link had discovered very large blocks that had been fastened together by iron clamps set in lead sockets. Link thought that these blocks might have been the remains of the colossal statues mentioned by Josephus, to adorn the harbors entrance.

In 1960, Link returned to Israel with a research vessel, Sea Diver II, a 28 m long steel craft suited with excavation, navigation and communication equipment. Working with aerial photos and the results of the divers surveys, Link was able to construct the basic plan of the submerged remains. The expedition also discovered a small medallion or token, identified by various scholars as depicting the harbor of Caesarea at its inauguration (10/9 BCE). The reverse of the medallion depicts a scene of a harbors entrance flanked by colossal statues, and the Greek letters KA in the upper field. However, this token may have been struck in Alexandria, perhaps in the reign of Antonius Pius (138-61) with no particular reference to Caesarea.

The Link Expedition to Caesarea was the starting point for years of underwater research carried out by the Israel Underwater Exploration Society (IUES), Caesarea Ancient Harbor Excavation Project (CAHEP) and Combined Ceasarea Explorations (CCE). In 1963, started the first international collaboration with Prof. Harold Edgerton from M.I.T. and his assistant Dr. Olivier Leenhardt, from the Oceanographic Museum at Monaco. The survey of the structures and wrecks buried under the sandy sea floor was made with Egertons invention "Mud Penetrater". This device was a low frequency echo sounder (12 kHz), which could plot submerged features. The "Mud Penetrater" was operated in the area of the sunken Herodian breakwater that had been surveyed previously by the Link Expedition. The results of the survey may be concluded as:

The coastline of the Roman era was at least 150-200 m further west of the present one. The divers have found two protruding high rocky blocks almost covered by sand, which might be the entrances towers.

2. The entrance to the ancient harbor is 350-400 m west to the northern Crusaders Wall tip, which is cut by the sea. The farthest part of the semi-circular breakwaters is more than 450 m from the present shore. One may recall that this was not a harbor dug on land such as Ostia, but an artificially built port in open waters.

3. Some stone blocks on the sea floor along the north and northwest lines of the sunken breakwaters are remains of artificial structures. Josephus tells about stone blocks that were thrown into water in large quantities and to a great depth.

In 1975-76, Avner Raban of Center for Maritime Studies (CMS), University of Haifa carried out an underwater survey in the outer Herodian breakwaters, for the Israel Electric Company. In 1979-89, the collaboration between A. Raban (CMS, University of Haifa) and Robert Hohlfelder of the University of Colorado, USA, founded the Caesarea Ancient Harbor Excavation Project (CAHEP). Other co-directors to joint the expedition were Peter Oleson from University of British Colombia, Canada, and Lindley Vann from the University of Maryland, USA and Raphael Stieglitz form the Rutgers University, USA. The project not only established that Josephus had described the breakwaters accurately but also recovered details on their design and construction.

The Joint Expeditions (JECM) and CAHEP had collaborated in the preparation of the Smithsonian Institutions exhibition "King Herods Dream", which was shown in Washington and than around USA from 1988-90. With this occasion was founded the Combined Caesarea Expeditions (CCE) under the direction of Avner Raban of the Leon Recanati Institute for Maritime Studies (RIMS) and Kenneth Holum of the University of Maryland, USA, that started work from 1989 since present. CCE extended the research of the northern sections of the western breakwater, known limits of the Hellenistic and Herodian Inner Harbor, the octagonal plan of an Early Christian church on the temple platform and the Early Islamic and Crusader dwellings within the Old City, the administration complex outside the Crusader Wall, and the Decumanus and also the northern part of the hippodrome (stadium).


Written sources

"Along the coast Herod discovered a city that was in decay named Straton’s Tower. The stretch of coast-line from Dora to Joppa, between which the city lies, was completely devoid of harbors, so that every ship sailing from Egypt along the coast of Phoenicia had to ride at anchor in open when menaced by southwest wind, for even a moderate breeze from this quarter dashes the wave to such a height against the cliffs that their reflux spread a great commotion far out to sea (JW 1.409)."

" Now the city is located in Phoenicia, on the sea-route to Egypt, between Joppa and Dora. There are small towns on the seashore and are poor harbors, because the southwest wind beats on them and always dredges up sand from sea upon shore, and thus does not permit smooth landing; instead, it is usually necessary from merchants to ride unsteadily at anchor off shore (AntJ 15.333)."

The site may be reached by the coastal highway, and Wadi Milek is the connecting way to Jerusalem.

Selected Written Sources

Historical development

The long history of Sebastos (Caesarea Maritima) stretches from Straton‘s Tower dated to the 4th century BC, the harbor constructed by King Herod (22-10/9 BC) and to the Late Byzantine period.


History of the Herodian Harbour

The information on the history of Caesarea and its harbor are found in the writings of Josephus Flavius: the Antiquities of Jews 15.331-39 and the Jewish Wars 1.408-15. Josephus had spent some time at Caesarea making detailed notes on the city and its harbor that was still functioning in the 1st century AD as much as it had in the last decade of the previous century (1st century BC).

Named by its founder Herod the Great in honor of Caesar Augustus (Herod’s patron), the city was the capital of the Roman province of Judea for about 600 years. To distinguish it from other cities with the same name and founded in the same period, it was also called Caesarea Maritima, Caesarea Palestina, etc. The port of Caesarea was named Limen Sebastos by Herod, Sebastos being the Greek equivalent of Augustus (in Latin).

In the 3rd century BC, during the Hellenistic period, the sandy hills along the eastern Mediterranean were given by the Persians to the Phoenicians who built a small fortified anchorage which they named Straton’s Tower. There is a common assumption that the name Straton is the Greek form of the Phoenician name Abdashtart (the name of two or three Sidonian kings). Another assumption is that the town was named after its founder, translated literally into Latin as Stratonis Turris and into Hebrew, Migdal Śar. More likely it seems that a Ptolemaic king founded the city with an anchorage and named it after one of his generals (a general named Straton served Ptolemy II, but he is not the founder of Straton’s Tower. Straton can also be a military title. In the Hellenistic citadel of Jerusalem, there was a tower named Straton, but it did not have any relation with the coastal settlement).

At the end of the 2nd century BC, Zoilos the tyrant of Dor, conquered Caesarea but it soon fell to the Hashmonean Alexander Jannaeus (100 BC). It seems that the first Jewish community was founded there during this time, but the rabbis excluded it from the borders of Palestine. To weaken the Hashmonean kingdom, Pompey annexed Straton’s Tower and other coastal town to the Roman Syria in 63 BC. The town was in a state of decay when Octavian, the future Caesar Augustus restored it to the Jewish state in 31 BC.

Between 22 and 10/9 BC, Herod built Caesarea on the site of Straton’s Tower. Above the main harbor and just to the east, Herod built a spacious platform upon which he erected a temple dedicated to the goddess Roma and the deified Emperor Augustus. Herod resettled the city with Jewish population as well as Greek speaking pagans. Caesarea became a typical city-state (polis) of the Hellenistic age, ruled by a city council and magistrates under a royal resident general.

When the Romans annexed Judea to the empire in AD 6, they made Caesarea the headquarter of the provincial governor and his administrative center. A Latin inscription found in the theatre records that Pontius Pilatus, prefect of Judea, dedicated a temple at Caesarea to the Emperor Tiberius. The city remained the capital of Judea, later called Palestina, until the end of the Byzantine period. In AD 66, in the eve of the First Jewish Revolt, Vespasian stayed at Caesarea and used it as his main base. After he became emperor, and in gratitude for his loyalty, Vespasian refunded the city as a Roman colony. In the 2nd and 3rd centuries, the city continued to profit from its links with the Roman emperors. Hadrian, who paid an imperial visit at Caesarea in AD 130, expanded the city’s aqueduct system and probably he also built the city’s stone circus. In response, the citizens dedicated a temple to Hadrian, and coins from the local mint depicted him as the colony’s founder. Other imperial visits were made by Septimius Severus in 199 or 201, and perhaps Severus Alexander in 231-232.

Christianity was founded at Caesarea within a few years after Jesus’ Crucifixion, when Saint Paul converted the Roman Centurion Cornelius (Acts 10). From the late 2nd century there is a renewed record of a Christian church with its own bishop. In the same period Jews resettled at Caesarea, being attracted by economic advantages. By AD 250, the city had a celebrated rabbinical academy and the Christian school of Origen, the outstanding scholar and theologist who assembled the famous library and compiled the hexapla text of the Bible. Within the Christian Empire (AD 4th-7th centuries), Caesarea’s population and economy expanded, as well as in the rest of Palestine.

In the Byzantine period, a new fortification wall enclosed a much larger urban space. The authorities built an additional aqueduct system (low-leveled covered aqueduct) and they continued to replace the city’s street pavements, following Herod’s original grid plan. When Christianity became the dominant religion, a church replaced Herod’s temple to Roma and Augustus on the temple platform.

In AD 530, the Roman emperor Justinian, promoted the governor stationed at Caesarea to proconsul. The city’s bishop also ranked as metropolitan of Palestina and Caesarea kept this prerogative even after AD 451, when the archbishop of Jerusalem obtained the rank of patriarch. The most famous bishop of Caesarea was the ecclesiastical historian and apologist Eusebius (bishop, AD 315 – 339), who recorded martyrdoms in the city’s amphitheatre under the last Roman emperor. Eusebius’ contemporary was Rabbi Abbahu, who taught his daughters Greek, visited the city’s baths and maintained excellent relations with pagan authorities. Another famous personality and result of city’s learned culture was Procopius of Caesarea (6th century).

By AD 500, tectonic actions and coastal surge had reduced parts of the Herodian breakwaters that became submerged reefs, being a hazard to navigation. The Emperor Anastasius (AD 492-517) undertook a major campaign to restore Sebastos, helping Caesarea to reach its high prosperity in the 6th century. During the 5th and the beginning of the 6th century, the relationship between the Christian majority and the Samarian and Jewish minorities deteriorated, and several conflicts took over by burning down the Church of Saint Procopius. These troubles presaged the invasion of the non-Christians in the 7th century. In AD 614, Persian army attacked Caesarea, but the city capitulated without serious resistance. The Roman army returned for a brief period in AD 628, but in 642 Caesarea fell to the Arab army after a seven months siege. Between the 7th and the 9th centuries, Caesarea suffered of heavily depopulation, buildings collapsed, the stone robbing took over and the harbor fell in disuse. By the 10th century, Caesarea re-emerged a prosperous town but on a much smaller scale. The Arab and Persian geographers el-Muqaddas and Nasir i-Khusrau, mention flourishing gardens and orchards, a fortification wall and a great mosque, apparently situated on what had been the Herodian temple platform.

In 1101, the Frankish king Baldwin I of Jerusalem and the Genoese fleet conquered Caesarea after a brief siege, and established a Crusader principality that lasted until 1265 (despite periods of reconquest). A Christian church replaced the Great Mosque on the temple platform. In 1251-1252, the French king Louis IX (Saint Louis) built the city’s fortification walls by "his own hands". In 1266, the Egyptian sultan Baybaras stormed Caesarea and in 1291, his successor leveled the city and other Crusader castles along the Levantine Coast of the Mediterranean. From time to time a squatter settlement existed among the ruins, but after 1291, Caesarea mostly remained desolated.


Construction of the Herodian harbor

The Herodian harbor at Caesarea is one of the first kind in which Vitruvius descriptions (V.12. 4,5) for the use of hydraulic concrete in harbor construction were applied. The harbor was composed of three basins, one inside the other:

  1. The inner most was built on the basin made by the Phoenician inhabitants of the Stratons Tower, in the southwestern part of the city.
  2. The middle basin was in a natural bay protected from the N and S by rocky promontories.
  3. The outer basin is the largest of three, was artificially created by constructing breakwaters to enclose a vast area of open sea.


Historical Reference on the Construction of the Harbor

Although, such unfavorable conditions of the Israeli coast, Herod was determined to construct a magnificent harbor at this site, to serve as a commercial link between the Roman Empire and also serve the capital of Jerusalem. The construction of the harbor appears almost identical, both in the Antiquities of Jews and the Jewish Wars:

"Having calculated the relative size of the harbor (limen), he let down some blocks (lithoi) into the sea to depth of 20 fathoms (c.20 m). Most of them were 50 feet long (15.25 m), 9 feet high (2.7 m) and 10 feet wide (3.05 m), some even larger. When the submarine foundation was finished, he then laid out the moles (teichos) above the sea level, 200 feet across (c.61 m). Of this, a 100 foot (c.30 m) portion was built out to break the forces of the waves, and consequently was called the outer barrier (prokomia). The rest supported the stonewall (teichos) that encircled the harbor. At intervals along it were towers (pyrgoi), the tallest and most magnificent of which was named Drusion, after the stepson of Caesar. There were numerous vaulted chambers for the reception of those entering the harbor, and the whole curving structure in front of them was a wide promenade for those who disembarked. The entrance channel faced north, for in this region the north wind always brings the clear skies. At the harbor entrance were colossal statues, three on either side, set up on columns. A massively built tower (pyrgos) supported the columns on the port side of boats entering harbor, those on the starboard side, two upright blocks of stone yoked together, higher than the tower on the right side (JW 1.411-13)."

"To correct this drawback in the topography, he (Herod) laid out a circular harbor (limen) on a scale sufficient to allow large fleets to lie anchor close to shore, and let down enormous blocks of stone (lithoi) to a depth of 20 fathoms. Most were 50 feet long, not less than 18 feet wide and 9 feet high. The structure, which he threw up as a barrier against the sea, was 200 feet wide. Half of this opposed the breaking waves, warding off the surge breaking there on all sides. Consequently it was called a breakwater (prokomatia or prokomia). The rest comprised o stonewall (teichos) set at intervals with towers (pyrgoi), the tallest of which, quite a beautiful thing was called Drusion, taking the name from Drusus, the stepson of Caesar who died young. A series of vaulted chambers was built into it for the reception of sailors, and in front of them a wide, curving quays (apobasis) encircling the whole harbor, very pleasant for those who wish to stroll around. The foundations of the whole encircling wall on the port side of those sailing into the harbor was a tower (pyrgos) built up on a broad base to withstand the water firmly, while on the starboard side were two great blocks (lithoi), taller than the tower on the opposite side, upright and yoked together (AntJ 15.334-38)."

Selected Written Sources

The underwater archaeological research carried out for the last 22 years by CAHEP (Caesarea Ancient Harbor Excavation Project) and CCE (Caesarea Combined Expedition) confirmed most of what Josephus had written on the construction of the Sebastos Harbor. The width and overall outline of the Herodian quays are quite accurate, but his claim about the water depth is very exaggerated.


Port installations



The outer harbor was comprised of a wide curving breakwater that enclosed the basin from S and W, encompassing a water area of approximately 25 acres. The eastern end of the southern breakwater rests on a rocky promontory that was the southern boundary of the middle basin. The remains of this breakwater (c. 40 m wide), continued westward for approximately a length of 200 m before turning northward for an additional length of 300 m. The width of the fallen remains differ in the western fall, from 60-70 m at the beginning of the arc to 150-180 m near the head of the breakwater, at the northwestern edge of the harbor. In the southern part of the breakwater only a few ashlars of the quay survived. Approximately 30 m west of the base of the breakwater, and 80 m north of its inner side, a floor made of ashlars slabs, of which only a survived section of 4 x 12 m, was found at a depth of 4.9 m bellow the sea level. Presumably the floor was the northern edge of the quay separating the middle and the outer basins.

The body of the southern breakwater was built of conglomerate blocks that were poured in wooden frameworks (caissons). The average of the blocks are 1.8 x 3.9 x 3.9 m. They were placed on a bed of stone rubble. Underneath this bed appear to be a foundation structure also made of concrete blocks. The outer edge of the breakwater rests on long ashlars blocks, some of which reach a length of 5 m, arranged in header courses.

During the excavations seasons of 1990 1991, was found a huge tumbled mass of blocks, in area K (comprised of the northern tip of the main breakwater and the twin towers north of it). The blocks are scattered on an area of 25 x 35 m, at a depth varying from 1.5 m to 8 m bellow the sea level. The tumbled blocks were found on a platform of hydraulic concrete mixed with rubble that had been poured in wooden frameworks (caissons), Some of the wooden caissons survived to a height of 2 m. The caissons had external and internal walls.

Prokomia or Prokomatia (Subsidiary Breakwater)

A well defined wall built of ashlars blocks and rubble, and incorporating few large masses of concrete blocks, branches off the southern face of the southern breakwater, close to its east end. This feature extends for c.130 m in a straight line to the NW. The upper surface of this structure is found at a depth of 6 m bellow the sea level. The width varies from 4 to 8 m and usually it rises 1 to 2 m above the sandy bottom. This wall is not an accidental structure created by the destruction of other features related to the main breakwater. This wall of a segmented line, being placed about 20-30 m outside the spinal wall of the southwestern breakwater, would cause the breaking of the surge and also absorb the waves energy. In his writings (JW 1.411-13; AntJ 15.334-38), Josephus mentions of an outer breakwater that he called prokomia or prokomatia (a subsidiary breakwater). The main role of this breaker was to prevent the splash of the seawater over the spinal quay wetting the vaulted stores. This feature also would ease the destructive impact of under-trenching currents at the base of the main breakwater. Being a segmented line with openings for rip currents, it would prevent the pilling up of seawater on the lee side and also keep it silt free. It seems that this unique structure was only added to the main breakwater, which faces the open sea and the full impact of the surge from the W and SW. This extra breakwater still remained almost intact, though it subsided 5-6 m.

The Northern Breakwater

The northern breakwater was a long rectangular structure projecting almost 240 m from bedrock shoreline towards the entrance channel. Its eastern base is rested on natural rock. Its width varies from 60 to 70 m, being covered (almost entirely) with small pieces of rubble. In the attempt to remove the rubble from the entrance area, large quantities of pottery and coins of the 5th-6th centuries were found. In addition, it was revealed that among the rubble large ashlars blocks were sunken at the entrance. Underneath the rubble wooden beams were discovered, probably to control the descent of the stone blocks on the sea floor. Carbon 14 tests indicate that the wooden beams age range from 1550 to 1700 years ago. Based on this information, the researchers assumed that the beams might be the remains of an attempt to rebuild the sunken harbor by the Byzantine emperor Anastasius (491 518). Near the head of the breakwater, protruding above the rubble of the Byzantine repairs are the remains of an enormous structure built of ashlars blocks 7 m long or more. Iron clamps were implanted in some of the blocks, to set them in place. They were implanted in lead cast in niches carved into the edges of the blocks. Remains of lead flows on the sea bottom (at a depth of mare than 9 m bellow the sea level) indicate that the casting was made after the stone blocks were placed under the water.

On the outer side, near the tip of the northern breakwater was found a rectangular concrete block. This block was poured into a double-wall wooden form (caisson). The dimensions of each formwork were 15 x 21 m. It seems that the original height of the block was as much as 3 m. A pavement of rectangular stone slabs was placed on top of the concrete block.


The Towers

The towers on both sides of the harbor entrance had been settled on sandy bottom. It seems that the western towers also served as sand catchers to prevent the silting of the harbors entrance. Also flushing currents kept the harbor channel silt -free and limited the accumulating sand bars on both sides in the open water.


Flushing Channels

With the completion of the quays, the harbor basin was enclosed and well sheltered from the surge. Within this enclosed basin was a setting body of still water, a terminal for the shifting sand and also a reason for gradual silting. In order to prevent or minimize such a natural process flushing currents were created, flowing out through the harbor mouth. Such a flush current was created by an inflow through a series of shallow channels transversely crossing over the southern mole. Each channel had its opening facing the surge with a base above the income waves to create a constant inflow of water. Such channels would feed the harbor basin with additional water. Vertical grooves for insertion of sluice gates would enable proper control over the rate of the inflow in various sea conditions. The additional quantity of water would find a way out through the harbor channel, flushing it properly. Confirmation for the successful flushing of the harbor basin was found on the sea floor. Within the main basin, under layers of wave carried deposits there was a thin layer of fine mud with some 1st century pottery shards on it. Such sediment is typical of still waters and represents the time when Sebastos was fully operational. The absence of sandy particles in the mud indicates that there was no silting of the harbor from the open sea. Probes carried outside the harbor mouth revealed a deposit of over two meters thick of mud, dirt and all sorts of garbage from the harbor, some kind of dumping site for whatever was carried away by that overflowing flushing currents.


Presumed Lighthouse at Caesarea

Josephus described the general harbors outline in both his works Jewish Wars (I. 408-418) and Jewish Antiquities (XV. 335-341). He also mentions about towers to be built on the main quay and the tallest and most fabulous was called Drusion:

"At intervals along it (the quay), were great towers (pyrgoi), the tallest and most magnificent of which was named Drusion, after the stepson of Caesar (JW I. 411)"

"The rest comprised a stone wall (teichos) set at intervals with towers (pyrgoi), the tallest quite a beautiful thing, was called Drusion, taking its name from Drusus, the stepson of Caesar who died young (AntJ XV. 335)."

In none of his writings, Josephus does not mention of a lighthouse at Caesarea. He is also less precise about Drusion, the only monument in the port facilities, other than the Great Temple that was dedicated to the goddess Roma and the deified Emperor Augustus.

If we try to reconstruct the lighthouse at Caesarea, than we must relay on other known Hellenistic and Roman similar structures. The famous neighbor Pharos at Alexandria may have been used as a model: three-tired structure with a square base, octagonal superstructure and a cylindrical turret. The reconstructed lighthouse at Caesarea would have been also based on other Herodian towers and known Roman lighthouses.


Port Installations


The middle basin

The Middle Basin (200 x 200 m) is located east of the Outer Basin. To the north and south it is enclosed by rocky promontory and to the east by the round tower and the wall of Straton’s Tower. On the northern side of the basin are found ashlars structures that during the Hellenistic period may have been used as shipyards or nauscenae. At the sea level are the remains of a "finger" quay that continues to he west. The quay made of narrow elongated ashlars (2 x 0.4 x 0.5 m) is a little more than 4.5 m wide and the surviving length is more than 10 m. On the southern side of the basin, the inner face of the Herodian quay survived to the sea level. Soundings at the base of this quay demonstrated that it is partly founded on natural rock and partly on an artificially poured conglomerate.


Sluice Gates and Flushing Channels

On the southwestern edge of the rocky promontory a channel was carved in the rock, leveled at 20 to 30 cm above the sea level. The sides of the channel have vertical grooves in which wooden gates could be placed to control the water flow into the channel. From plans drawn by researchers of the Palestine Exploration Fund in the 19th century, it seems that there were other channels east to this one. Their function was to force a surplus of water into the harbor and thus, create a constant flow from the entrance channel onward. This flow would ensure the removal of sediments from the bottom of the harbor, to prevent sand and silt from penetrating through the entrance. Proof that such a flow existed was found in a layer more than 1 m thick at the mouth of the harbor. The layer contained muddy clay and an abundance of pottery, metal parts of ships and gravel that drifted there from the bottom of then-active harbor.

Other remains of the Herodian construction on the southern side of the Middle Basin are today covered by structures of the Crusader harbor fortress and the concrete of the modern wharf.


The inner basin and vaulted warehouse

Josephus describes the inner harbor as "having deep anchorages in its innermost recesses for ships and goods".

In the excavations carried out by A. Negev in 1962, a large arched vault was exposed, cleared and identified as a warehouse, belonging to the Inner Basin. The excavations carried out in 1976 revealed that the eastern quay of the inner basin runs for about 250 m, on the SSW-NNE axis. Major excavations carried out in the Inner Basin between 1991 and 1996, revealed its most part, but constant excavations still go no. Excavations made on three sides of the original quay made possible to identify the extent of the basin within the limits of the inner harbor. To the south, the course of the quay is very similar to that of the Crusader fortification, and it runs for about 150 m from the present diving club to the southeast (near the South Gate of the Crusader City).


The excavations carried out in 1976 revealed that the eastern quay of the inner basin runs for about 250 m, on the SSW-NNE axis. Major excavations carried out in the Inner Basin between 1991 and 1996, revealed its most part, but constant excavations still go no. Excavations made on three sides of the original quay made possible to identify the extent of the basin within the limits of the inner harbor. To the south, the course of the quay is very similar to that of the Crusader fortification, and it runs for about 150 m from the present diving club to the southeast (near the South Gate of the Crusader City).

On the east, the course of the quay is not linear and it changes direction to the north. Its total length is about 280 m. At the north corner the quay changes direction westward in a diagonal line. At this point the structure confining the inner basin is not a quay but a solid retaining wall to the elevated sandy beach behind. The north wall built of ashlars blocks continues from the retaining wall towards the sea for about 139 m (at the northwest side of the present-day bathing beach).


To the west, the inner basin was separated from other parts of the harbor by a wall running from the northern part of the natural bay up to 40 m, where it ended with a circular tower, 13 m in diameter. Remains of the tower were found during previous seasons of excavations.


Construction Phases of the Inner Harbor

Hellenistic (pre-Hellenistic, 2nd century BC): A partially rock-cut basin forms the inner basin. A quay built of stones east, appears as a wall.


Herodian period (end of the 1st century BC): During this period repairs were made on the quay and sea walls around the inner basin. Vaults are built in front of the kurkar hill, which, is surrounded by a wall. The vaults are also used for the temple platform. On the eastern side of the Herodian quay, a mooring stone was found on the vertical face and also a flushing channel, on N-S orientation, was exposed at the southern side of Inner Basin.


A staircase led from the harbor to the temple platform. The foundation of this staircase built into ground water level, was revealed beneath the Byzantine stairs. Its method of construction is similar to that of the Herodian breakwater.


Late Roman period (2nd-3rd century AD): Evidence suggest that the main quay of Sebastos lost its effectiveness towards the end of the 1st century CE, thus allowing sediment deposits carried by wave energy to accumulate into the inner harbor. At the end of the 2nd century AD, the inner harbor was already partly silted, nonetheless the Romans made some attempts in using its eastern section. This included an extension to the Herodian quay, 8 m wide and 21 m long. The flushing channel to the SE was blocked as a result of the Roman attempt to deepen the eastern part of the harbor.


Late Roman-Early Byzantine period (3rd-5th centuries AD): The excavations did not reveal any structures dating to these periods and connected with the activity of the inner harbor. It seems that large parts of the inner basin were sand-locked. Drillings and excavations carried out in the areas I/9 and I/14 revealed a thick layer of organic material. The top of the layer lies 0.6 m below the sea level, while its base laid on bedrock and a thin layer of sand (2.3 m below the sea level). Pottery shards found in this context date to the late 3rd - early 5th centuries AD. It seems that during the Late Roman period and probably till the mid 5th century, the inner harbor continued to decay by the accumulation of urban residue and waves carried sediments.


Middle Byzantine period (500-550 AD): The repairs and reconstruction of the vaults that were made during this period are attributed to Anastasius. The building project on the east side of the harbor basin included a garden, drainage channels, paved areas and a "reflective pool" fed by ground water found at the foot of the Herodian quay. The east quay was raised and widened. A column inserted in the quay was used as a mooring stone, presumably in the period when the water basin was deep enough to allow small vessels to anchor near the quay. The podium was raised and widened, serving as the setting ground for the octagonal church.


Later Byzantine period (550-640 AD): As a result of marine transgressions, the inhabitants were forced to elevate the surface of structures built in the harbor basin. The "reflection pool" and the garden were covered by massive amounts of fill. Buildings and storerooms were built on top of this fill. By this time the inner harbor was totally sand-locked.


The caissons and building phases of the Herodian harbor

Bottomless Wooden Caisson at the Northern Breakwater and at the Eastern Tower

To understand how these caissons were constructed and used for building the breakwater, we have to relay on the paragraph where Vitruvius (5.12.4) describes the method how to set up formworks in rough seas. He also proposed a method of preparing and curing concrete blocks on land for the breakwater that would be transported to site by the natural forces of beach-movement. This method is not relevant because there is no control to where the blocks would have been taken by the surge. In the following paragraph he describes how to built a double walled cofferdam (5.12.5) to construct a pier:

"Let double-walled formwork to be set up in the designated spot, held together by close set planks and tie beams, and between the anchoring supports have clay packed down baskets made of swamp reeds. When it has been well tamped down in this manner, and is as compact as possible, then have the area bounded by the cofferdam emptied and dried out by means of water-screw installations and water wheels with compartmented rims and bodies. The foundations are to be dug there, within the cofferdam."

The cofferdam described by Vitruvius, may by applied in shallow water and in close vicinity of the shore. The wooden forms used for the eastern Tower and the western tip of the northern breakwater is a combined result of Vitruvuis description and the physical conditions at Caesarea. The bottomless double-walled formworks were built on the shore. A liquid hydraulic mortar was poured between the walls of the caisson, about 1/3 or half height and let to dry. The density of the dried concrete was 0.6, thus it allowed the caisson to float. When dried, the caisson was floated to its final position. Once the form was anchored by heavy chains by the divers, mortar was poured into the sections of the hollow walls with careful attention to balance, until the buoyancy of the wood was overcome, and the form settled into position on the prepared surface. While the inundated compartments of the form were filled with mortar and aggregate, rubble was also dumped around the periphery of the form to prevent its shifting prior to curing of the concrete, or undermining of the final block. The use of caissons system would allow a rapid and flexible schedule of harbor construction.


Box Caisson

This process of building caissons on the shore and installing them as compartments for an artificial island seems to correspond with the eye witness testimony of Pliny the Young, in one of his letters (1st century CE), written from the Roman coastal town of Centumcellae.


Building Materials

The underwater excavations carried out on the breakwaters revealed a very complex technology of building and the most, the use of hydraulic concrete called pozzolana [actually the volcanic ash was called pozzolana; lime mixed with volcanic ash (pozzolana), being in contact with water or sea water, made the hydraulic concrete, that enabled the Romans to built bridges and harbor jetties]. Herod imported all the construction materials (wood, marble, glass, lead, etc.) and especially pozzolana, to build his unique harbor. Constructing the harbor, Herod wanted to create a safe shelter for large fleets "to lie anchor close to the shore" as well as quays for activities of loading and unloading the cargo from the anchored merchantmen. It seems that the outer basin was designed to accommodate passing fleets; probably the great grain fleets sailing from Alexandria to Rome.


The Roman hydraulic concrete that hardens underwater is described in Book (a ten volumes work; De Architectura), written by Vitruvius, in 25 BC. In this book he describes the origin of pozzolana and its use to make the concrete for structures and piers:

"There is a powder which, by nature produces wonderful results. It is found in the neighborhood of Baiae and in the lands of municipalities round Mount Vesuvius. This (pozzolana) being mixed with lime and rubble, not only furnishes strength to other buildings, but also, when piers are built in sea, they set under water And there would not be unless deep down they had huge blazing fires of sulphur, alum or pitch. Therefore the fire and vapors of flame within, flowing through the cracks, make that earthlight. And the tufa, which is found to come up there, is free from moisture. Therefore, when three substances formed in like manner by the violence of fire come into one mixture, they suddenly take up water and cohere together. They are quickly hardened by the moisture and made solid, and can be dissolved neither by the waves nor the power of the water."


Building Phases of the Harbor

The underwater archaeological researches carried out at Caesarea Maritima have revealed much of what Josephus did not see. The great breakwater had subsided through the centuries and what was originally at the water level is nowadays over 5-6 m bellow the sea level.

During the 1990-91 seasons, the divers discovered a series of wooden forms in which aggregate of pozzolana had been packed. One such form which had survived almost intact in its lower part was 14 x 17 m, and with its original height of 4 m, probably the depth of the sea floor at that site at the time of the construction. The discovery of more such concrete blocks poured in wooden caissons and the results of the previous investigations in the construction of the Herodian harbor, made possible to sum-up a general assumption on the construction phases:

Phase I

The first feature to built in the open sea was probably an artificial island, where eventually the main breakwater would be, some 500 m N-NW of the southern promontory (100 m long, 20 m wide) and about 350 m west of the stem of the northern breakwater. The island was built by a series of wooden formworks (caissons) packed with hydraulic cement (pozzolana, lime and rubble). The forms had been constructed on the shore in the traditional shell-first shipbuilding technique of that period. Than, each form was towed into position in the open sea and moored by iron chains in all four corners. The caissons were set as close as possible, thus to create a large platform. When the process of setting the caissons was finished, additional loads of pozzolana, lime and rubble were added into the caisson from barges, so as to cause a gradual even subsidence till it rested on a rubble cushion that was previously prepared on the sandy sea floor. The sides of the forms were retained with piles of rubble and the gaps between the caissons were filled with pozzolana packed in sacks. The combined platform, probably 30 x 60 m, was covered with paving slab stones, on which a large tower was built, probably the "Drusion" mentioned by Josephus and the assumed lighthouse. Another artificial island of a similar type of construction was placed half away long the perimeter of the main breakwater, at the turn of its course from west to north.

Phase II

The final phase

During this stage of building Sebastos, the southwestern and northern breakwaters were completed and the upper structures were built on top. Some of them were observed and described by Josephus. Towers and the vaulted stores were built on the spinal (main) quay. Subsidiary jetties were added dividing the harbor into three mooring basins, one within the other. Remains of a quay and jetty are found beneath the modern quay built atop about forty years ago.

At the tip of both breakwaters of the main basin there are huge masses of tumbling blocks, remains of the elaborated superstructures that crowned the harbors entrance. Some of these large blocks are over seven meters long. Other stones were carved with a hemispheric socket for wooden shafts for capstans on which, probably chains were rolled up across the entrance. In order to withstand the drag of the pulled chains the blocks were fastened to each other with iron clamps fixed in molten lead that was poured into cut grooves in the stone. Solidified flows of molten lead, which were found at the foot of the tumbling mass, 10 m bellow the sea level, indicate that the lead had been poured after the blocks were laid in place in the water. For such work, divers were needed to work underwater probably using snorkels for breathing. Such professional divers were known in the Roman world as urinatores.


Caesarea - Sebastos in the late Roman period

The subsiding of the Herodian breakwaters created an underwater obstacle that prevented the use of the basin to its east even as an open anchorage. On top of the main breakwater were found several concentrations of broken amphorae and ballast stones, evidence that ships were wrecked while trying to sail over this sunken reef (breakwater), on their way to the shore. The 4th century remains, provide the latest date of the final submergence of the Herodian harbor. During this period, the bay to the south was apparently used as a semi-protected anchorage area, where ships loaded and unloaded merchants in small boats (lighters) that, carried them to be stored in the vaulted barrel warehouses on the coast. These structures also formed the raised area of hanging gardens of the Byzantine and Arabic periods.


Related Artifacts

On top of the northern part of the main breakwater (Area K 5), was found a group of five lead ingots that were cast in the same form (each ingot weighted from 60 to 70 kg). They have a trapeze cross-section and on top are found an elongated Latin inscription "IMP.DOMIT.CAESAR.AVG.GER.". The inscription is related to the Emperor Domitianus (81-96 AD); he earned this title after his victory in Germany, in 84 AD. These ingots probably were cast in the late 80s or the beginning of the 90s of the first century AD. The other inscriptions found on the sides of the ingots relate to the weight of 200 Roman Libra. The inscription "MET.DART." (Metalia Dardanica), is found on all five ingots. It attests the origin of the lead and silver mines within the Roman Empire; such a place was Dardania, within the Cosovo area, near Bosnia. The date of the ingots indicates the exact period when the ship wrecked and also the date of the ruined Sebastos, in the late 1st century AD, about one hundred years after its building and inauguration.


The Crusader harbor

The Crusader harbor occupied part of the Middle Basin of the Herodin harbor. It seems that during this period the sea level was one meter lower than today, and the Inner Basin was filled up with rubble and silt accumulation west of the round tower. On the sea floor, 30 m west of the tower, another rectangular one was discovered, which was similar in dimensions to those of the Crusader fortress. A wall (N-S orientation), meets this tower from the north; its width at the base is 4-6 m. The western face of the wall is preserved for a height of five or six courses, being built in the similar technique as the outer walls of the Crusader City.

The principal component of the Crusader harbor was the harbor fortress, built on the base of the southern Herodian breakwater. The fortress was separated from land by a wide moat that cut the base of the breakwater on both sides (perhaps at the point where flushing channels had previously existed. Between the base of the southern breakwater, east of the moat, and the submerged tower was an entrance (40 m wide), connecting the city to the harbor.


Columns Jetty

From the northern end of the north wall on the shore, a quay built of Roman granite columns in secondary use, was laid to the west. The columns were placed next each other on top of a rocky abrasion shelf and the gaps between were filled with stone construction and mortar. The jetty extends to the west for 100 m and than turns to S-SW. Most of the southern part of the jetty is submerged beneath the sea level (0.20 0.30 m in calm sea), as a result of the collapse of its stone foundation. Additional remains of this jetty have been found for another 40 m along its original line.



Holum G. K., Hohlfelder R. L., Bull J. R., Raban A., 1988: King Herod‘s Dream: Caesarea on the Sea; W. W. Norton & Company, New York - London

Negev A. and Gibson S., 2001 (revised and updated ed.): Archaeological Encyclopedia of the Holy Land; Continuum, New York - London

Oleson P. J., 1985: Herod and Vitruvius: Preliminary Thoughts on Harbour Engineering at Sebastos; the Harbour of Caesarea Maritima; in: Raban A. (ed.): Harbour Archaeology: Proceedings of the First International Workshop on Ancient Mediterranean Harbours, Caesarea Maritima, 24-28.6.83; BAR International Series 257

Raban A. and Oleson P. J. (gen. Ed), 1989: The Harbours of Caesarea Maritima: Results of the Caesarea Ancient Harbour Excavation Project. 1980-1985; Part i and ii; BAR International Series 491

Raban A. and Holum K. G. (eds.), 1996: Caesarea Maritima A Perspective after Two Millennia; E. J. Brill; Leiden, New York, London

Vann L. R., 1991: The Drusion: a candidate for the Herod’s lighthouse at Caesarea Maritima; IJNA 20.2: 125-139

------------- (ed.), 1992: Caesarea Papers: Straton‘s Tower, Herod‘s Harbour, and Roman and Byzantine Caesarea; Ann Arbor, MI

Whiston W. (translated), 1991: Josephus Flavius: The Complete Works of Josephus; Kregel Publications; Grand Rapids, Michigan 49501



Zaraza Friedman


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