The Hjortspring Boat

See this text in

The Hjortspring Boat is an early Scandinavian example of a plank built vessel. It is firmly dated within the Early Iron Age, but its resemblance with the abundant rock carvings and bronze ornaments depicting ships from the Scandinavian Bronze Age shows how these should be interpreted - as plank built light boats propelled by paddles. The boat is part of a war-spoil deposition in what is today a peat bog, but in antiquity was a lake.

The Hjortspring site and research history

In 1920 the Danish National Museum received notice that several decades earlier finds of weapons and a large boat was made during peat cutting for fuel in the Hjortspring bog on the Island of Als. The museum excavated the boat and its associated weaponry during two seasons in 1921 and 1922. <here image 006t004.jpg> Much of the boat and the other finds was damaged by the frequent peat cutting, but due to the skills of the excavator, conservator Gustav Rosenberg, it was possible for Fr. Johannesen - who also worked on the Gokstad and Oseberg Viking ships - to reconstruct the boat with a high degree of certainty. <here image 006t001.jpg>

Rosenberg was responsible for the conservation of the waterlogged finds, which he did to the best of standards by the time. Nevertheless it was necessary to retreat the find prior to the new display of it that was opened to the public in 1988 in the Danish National Museum in Copenhagen. This work also called for a new and more reliable dating of the find, since this hitherto was purely typologically based. This was done by opening Rosenberg's old trenches and recover some left over wood and date it by radio-carbon. The result states the period 350-300 BC as the most likely age.

Constructional features of the Hjortspring Boat

Five large lime-wood planks make up the most of the boat. According to the reconstruction there is no keel, but a 15.3 m long - up to 50 cm wide - lime plank with carved out cleats for fastening of the frames. In either end it has a V-shaped section on which flanged stem and stern pieces are sewn. It continues a bit fore and aft of these to form bases of the lower of the characteristic double protrusions. Whether the bottom plank has been expanded from a hollowed out trunk, or manufactured directly to shape is not possible to establish. On each side the bottom plank has two lime planks of equal dimensions all of which are sewn together with lime bast rope. The planks are up to 65 cm wide and in single pieces - 15 m long - and only 2 cm thick. Every one m the first planks have four cleats and the second planks two, for fastening the frames. Above the uppermost frame-cleats on the second strake are crescent-shaped cleats that hold the thwarts in place.

The hood ends of the four side planks are fastened to the flanged stem and stern pieces, which are carved from solid trunks or forks to light horizontal V's. In this way the extremities of the gunwale are made up by the top of these pieces, and here they continue in Y-shape to form the uppermost of the protrusions. The upper protrusions are T-shaped in section, where the lower ones are oval. Immediately outside the stem and stern pieces they are connected by vertical locking boards. About one meter outside the stem and stern pieces the protrusions are once more connected by lighter boards with incised zigzag patterns. Four cleats are carved out of the stem and stern pieces just inside of the locking boards.

Overall the boat has been about 19 m long, from stem to stern some 13.3 m. Its beam is reconstructed to 1.9 m and its height to 0.7 m.

The stern area is covered by a poop made up by two lime boards cut to fit the curves of the planking. On its fore edge is a zigzag ornamented cross beam.

The framing system consists of 10 stations exactly one m apart. A hazel branch is bent and lashed to the cleats on the planks. On its way from one gunwale to the other it goes through one side of the thwart, then through an eyelet in a cross-beam, two thwart stanchions, the other eyelet of the cross-beam and finally the other side of the thwart. The thwarts are carved from lime and have two curved seats which are slanted slightly outwards to give the warriors the best paddling position. Between the frames the plank seams are covered with light boards.

Several of the paddles have been found, among them were two considerably broader ones which might have been used for steering by a helmsman most likely sitting on the poop.

The Hjortspring Boat and the Nordic clinker tradition

Being the oldest plank built vessel in Scandinavia, the Hjortspring Boat offers clues to the solution of some of the basic problems in the ship archeology of the region. The interpretation of the Bronze Age ship depictions have been much debated, mainly dividing the opinions in two groups; one following a skin-boat theory and the other believing that they are images of wooden boats. The striking resemblance between the Hjortspring Boat and the Bronze Age pictures have been questioned, but today after the re-evaluation of the find, Johannesen's reconstruction remains with only minor additions.

The skin versus wood discussion has also been part of the search for the origin of the Nordic clinker built boat. With the validity of the reconstruction of the Hjortspring Boat we have a plausible line of development from the simple log boat to the log boat with sides extended by planks. This turns into boats of the Hjortspring type, which essentially is a log with two added strakes of planking. In time the planks grow in number and the log turns into a proper keel. This corresponds well with the shell-based way of designing boats in the Nordic tradition, where the frames are inserted after the planking.