The “Five finger” docks, erected in 1758–1856, were the result of Augustin Ehrensvärd’s proposal for the Navy’s warships to be kept in roofed dry docks when not needed for active service. In 1757 plans were drawn up for the construction of a massive naval arsenal and 31 docks in Karlskrona. The docks, spread in a fan formation, were to include two berths and two large mast cranes, but in the end only the “Five finger” docks were built.

The Old Mast Crane. The mast crane was built to serve the Five finger docks and work on the construction was begun in 1803. The main structure of the 42 metres high crane is of brick and the top section of wood covered with copper sheeting. It was used to demast the ships before they were taken into dock and a team of 96 men working on four capstans was needed to draw up the heaviest loads. The crane machinery is still intact.

The dockyard walls. When the Five finger docks were constructed and the dockyard area extended to the west, a plank wall was erected between the new dockyard and the town. This was later replaced by the massive present-day wall.