The archaic mole was formed by the extension of the city wall, which runs from E to W and protects the port from the north. This part of the wall ends at the sea, which is today traced by a layer of sand with shells and pebbles in the area where the sea basin stood. The foundation of the wall made of rubble that was found was probably built at the level of the sea surface. At the western end, where it meets the sea, it widens either to offer greater protection or to serve as a basis for a tower.

Crusader Port

During the Crusader period no important work was carried out on the breakwaters or the sea walls. During the Turkish government the stones from the masonry at Atlit were shipped away to be used for building the sea walls at Akko, still surrounding the harbor.

Another tower was built at the northern tip of the western jetty, connecting to the southern breakwater. In the writings of the Persian traveler Nasr Kursau (1047), is mentioned that a chain as a blockage was closing the entrance of the inner harbor during the night and against enemy attacks.

Dover was a very important Roman government crossing point to the European mainland and it was heavily defended by the Roman navy, the Classis Britannica, who had built forts there in the late 1^st and 2^nd centuries.

These were superseded in the late 3^rd century by a Saxon Shore fort, one of a number of later Roman coastal forts around south-eastern England, suggesting that it was the base of a naval fleet that operated during the 4^th century until the end of the Roman period in the early 5^th century.

The defences of Dover fall into two types: Roman and medieval fortresses, and a medieval town wall recently excavated near the seafront. The Roman forts lay at the bottom of the river valley close to the sea, and the medieval fortress, Dover Castle, lies on top of the high eastern hill.

There are two phases of Classis Britannica fort, each surrounded by a defensive stone wall rectangular in plan with rounded corners like a normal Roman military fort. The first fort was unfinished and was probably built not earlier than the late 1^st century AD.

The second phase of Classis Britannica fort was built on the same site about AD 130-140, and was finally abandoned about AD 210. Inside its defenses were rows of buildings beside a grid of streets.

The forts include many bricks and tiles stamped CL.BR in their construction.

The Saxon Shore fort also had a stone defensive wall, but was built in the late 3^rd century. The complete shape of that fort has not yet been revealed.

According to the ancient sources, the Spartans probably fortified Gytheion, as in 370BC, when the Spartan Epameinondas laid siege to the city was not able to destroy the Spartan ship-sheds. However, there is no archaeological evidence to support the existence of harbour fortifications.

According to the researchers Halieis is a small, man-made harbour, with the surface area of 4km². Two circular castles are located in the center between the Eastern and Western side of the city. There is a gap of 20m between them, one is located North than the other, and they both form the mouth of the harbour. From the Southern castle, almost vertical to the modern coast and direction towards the North, there is a mole that leaves between its northern end and the second castle a gap of about 9m. The opening bares cutting marks and probably closed with a boom.

The harbour of Lechaeon was, according to Strabo (VIII, 6, 22) and Xenophon (Hellenica, IV, 4, 5), well fortified and connected to the city of Corinth via ‘long walls’.

The eastern portion of the long walls was discovered during the excavations of the American School of Classical Studies (Parsons 1932, 84-125). According to the excavation results, the wall reached the eastern side of the eastern harbour mound (Parsons 1932, Fig. 55). Segments of the west wall were discovered in 1906 by A. Skias, which terminated to the west of the harbour (Skias 1907, 145-166).

The harbour was also fortified to the south, as mentioned by Diodorus Siculus (ΧΙV, 86, 4). These walls would have formed a protective ‘H’ shaped fortification on the three sides of the harbour of Lechaeon. It is also possible that the harbour was further fortified by a secondary wall facing the sea, and possibly north of the two mounds. There are still visible remains above the level of the eastern reinforcement wall, at the entrance to the harbour, that may well indicate this sea wall (Fig 11, 3).

On the retaining wall of the western’s entrance channel may be seen, according to Pallas (Pallas 1969, 201), a cutting that resembles the niches for a bridge, or possibly a system for the blockage of the harbour. Today, only the grooves that once held the metal clamps, for the connection of the stone blocks, are visible, and can be dated to the first construction phase in the Archaic period.

Die heute verlandete Hafeneinfahrt war ca. 100 m breit. Sie war durch eine Kette absperrbar (vgl. Vitruv XII 1), wie eine an der äußßeren Spitze der Ostmole erhaltene 2 m hohe Säule ( Durchmesser 70 cm) zeigt.

Although the city of Methoni was already fortified during the 5^th century BC (Thucydides II.25) there is no positive evidence for the fortification of its harbour until the 15^th century BC, when P. Bembo mentions that the Venetians undertook large-scale repairs at the fort and the moat. According to him the Venetians constructed a note-worthy fort at the harbour and created in the sea a dam, which did not let the hostile ships to sail near the city walls. However, they left a small gap that enabled the entrance of a single ship at a time, because for them it was easier to fight a single ship at a time, rather than a lot together (Lianos 1987, 132)

According to Lianos (1987, 134), during the underwater survey a gap around 20m wide was located, cut on small lime-stone reefs, on the southern end of the ancient mole, while the fort mentioned in the literature, can probably be identified with an earlier construction phase of the fort, now called Bourtzi.

The semicircular arrangement of the porticoes on either side of the "Diazeugma" and the adaptation of such an arrangement to the city’s Hippodameian plan points to the formation of an enclosure around the area of the "Emporion" (Steinhauer, G.A., 2000,p.91). The existence of the enclosure is noted on Judeich’s map (fig.10) with a length of 80m and foundations of such walls have been discovered near one of the porticoes (Dragatsis portico) and further north.

The naval zone was separated from the rest of the city –in the same way it did in Cantharus’ port – with an enclosure that run across its whole length at a distance of 50m from the coastline, serving in the same time, as the closed wall of the ship sheds’ narrow side.

The fortification of the city and the harbour, was established by Themistocles in 493 B.C., before the building of the city, with the two large city gates of entrance to Piraeus from Athens. "At this point, which bore the main weight of the city’s defense, was the thickest (5m) part of the wall, the strongest, most solid construction and the protection by a dense array of enormous circular towers 10m. in diameter" (Steinhauer, G.A., 2000,p.45).(Fig.18)

The gates are the most ancient feature of the Piraeus fortifications while different phases of construction can be identified in the surviving towers. In the remains of the towers that form the western gate, the round towers are attributed to the Themistoclean phase and the reconstruction by rectangular ones to that of Conon. From the walls that surrounded the city from the north, continued on the coastline and extended over the harbour entrances (as it has been described for each pot separately) the westward line of the northern wall, towards the Eetioneian coast, has been confirmed by a series of excavations retaining its solid construction and its width.

The third surviving gate that has been discovered, is the Eetionian gate, situated on the hill of Kastraki on the northwest side of the Main Harbour (Cantharus), overlooking the entrance to Piraeus from the sea." This is a simple type of gate (fig.21, 22), without a recess internal courtyard. It consists of an entrance (3.70m wide) with a two- paneled gate, flanked by two towers which were initially rectangular but which, very likely in the Hellinistic era, were enclosed in circular ones with a diameter of about 10m.The towers have been preserved today to a height of 3.00 and 5.00 meters respectively." (Steinhauer, G.A., 2000,p.48-49)

The walls that extend over the Eetionian coast (fig.19, 20) as well as the Eetionian gate have preserved at least three different construction phases.

The coastal walls that surrounded the peninsula of Piraeus are preserved today in quite good condition and to a length of approximately 2.5 kilometers from the entrance of the port of Zea to the entrance of Cantharus. The walls constructed by Themistocles (493-404 B.C.) were shorter in length than the surviving Cononian walls that were extended in order to cover the entire, perimeter of the peninsula, and avoid any possibility of landing. The cononian walls were constructed at a distance of 20-40m from the sea and was a lot narrower (3.10-3.40m) than that of the northern fortification of the city and the solid construction of the former was replaced by the "emplecton" method according to which, the two sides of the wall are constructed with blocks of carved stone and the inner part is filled with mud and rocks.

Remnants of the fortification of the harbour and the city are preserved on the peninsula of Piraeus, on the whole length of the Eetioneian coast, northeast of the city as well as behind the area of today’s Kastella. (Fig.23) At some points the wall is preserved up to the height of eight courses of stone and along a total of 2 kilometers (at intervals of 45 to 100m, according to the morphology of coastline), 22 rectangular towers (4x6 m) have been preserved. (Steinhauer, G.A., 2000,p.52). From the towers that formed the entrances to the ports one is still standing on the eastern side of Zea, as well as those of the port of Mounychia.

The military port was enclosed in ancient times within a marine wall, which formed part of the land wall. During the excavation a segment of the Byzantine wall was located 0.50m under the sea surface at the SE cove of the port. It was established that the foundation lies on top of the foundation fill of the ancient wall. Two segments were revealed, the first is made of three layers of transversal and horizontal limestone blocks, 4m wide, the second segment 1m underneath the foundation of the Byzantine wall is made of 17 transversal limestone blocks in two layers, 13m long. The second segment is thought to be the outer face of the marine wall that closed from the south the ancient military port.

The moles of the closed harbour are formed by the extension of the land fortification wall towards the sea and are partially covered by the modern quays. In the northern part of the port the marine wall starts off from the land wall, near the gate of the Goddess with the chariot, follows for 148.6m a SE-SW direction and then turns SW at a length of 45m (points A-B). The wall is 3m wide, and is made of a double row of schist slabs with rubble fill in-between, mounted with marble blocks, on rubble foundations. A part of it is preserved at a height of 2m. In the SW part the wall (points G-H) starts off from the marine gate and turns NE (points F-G) for 31m. During the excavation only its inner face was revealed. It is made of marble blocks in even layers and rubble fill; a part of it is also preserved at a height of 2.13m. The way blocks placed vertically are spaced every 2.40 to 2.50m in the segment F-G of the mole is very characteristic.

In the area between the points D-F the excavators estimate that the continuation of the marine wall is to be found and as a result they place the entrance of the port in the area between the points C-D. The restricted opening of the entrance at this point, namely 20m, would also account for the use of the term ‘kleistos’, translated enclosed or closable, in the ancient sources. It is very usual at this period to place the entrance of the military ports at an angle.

On the side of the ancient agora the excavators place another stress of the wall that separated it from the harbour area and through gates communicated with it.

During the Early Christian Times the plan of the port changes and the entrance is shifted to the point where it stands today. During this period a new part of the mole is constructed (points C-D and D-E) from architectural members in second use and roughly made columns. Its one end (point E), underneath the modern red light, is made of spolia joint with hydraulic concrete and is founded on an ancient construction, which consists of transversal and horizontal stone blocks joint with axe tenons (two have preserved the lead fill).

Lasting the excavation the already known mole of the commercial port, situated outside the fortification wall, was partially explored. It follows an E-W direction, is 115m long and 18-30m wide. At its W end it forms a semicircular area with a diameter of 20m. It is built with two rows of worked stone blocks, of greater size on the windward side, with central fill of marble and schist splinters. The superstructure is made of marble blocks, which were found misplaced or fallen on top of or round the mole. It is estimated that the mole was also fortified and that on the southern part there must have been a quay at the base of the fortification wall. The semicircular end is supposed to be a tower.

During the Hellenistic period the fortification wall of the closed military harbour was reinforced with circular towers at its angles. The existence of three of these towers is archaeologically attested. They form part of the general reinforcement program of the city instigated by the progress made during this time in the besiege techniques.

The tower at point G, with a diameter of 8m at its base, is preserved at the height of 6 layers made of marble blocks (height of layer from bottom to top: 0.40, 0.25, 0.15, 0.35 and 0.50m). Its interior has been filled with small stones and the excavators believe that there was no arrangement for interior free space. The tower was a donation of proxenos Heracleodoros, as is stated on an inscription associated with the building material of the tower (Et Thas V, 376).

The tower at point B, 10m in diameter, is today submerged. It is preserved at a height of three layers made of trapezoidal schist blocks (average length 2m/0.50-0.80m and average height 0.30-0.45m) and is founded on small stones. The excavators have traced an entrance at the point of its joint with the wall of the 5^th c BC, where a differentiation in the masonry is observed.

The tower at point C, 9.60m in diameter, is preserved at a height of two layers in shallow water. It is built with schist blocks of similar dimensions to those of the tower at point B, the lower of which, 0.35m high, projects 010m. Its position was associated to the existence of the entrance of the harbour at that point. It is also suggested that towers B and C had interior arrangements for war machines, i.e. catapults etc.

The existence of a tower at point F, which is mentioned in the preliminary reports of the excavation, is considered, according to new evidence yielded through additional research, to be uncertain.

Zwei ebenfalls aus dem Felsen gehauene Steinsäulen, jeweils an den Molenenden gelegen, dienten zum Verschließen der Hafeneinfahrt mittels einer Kette (vgl. Leptis Magna).