Orlogsværftet was a Danish naval shipyard under the Royal Danish Navy. Before 1924, it was an integral part of the naval base at Holmen in central Copenhagen, Denmark, with an independent management from 1692 when Olaus Judichær became the first factory director.

The Type 205 was a class of German diesel-electric submarines. They were single-hull vessels optimized for the use in the shallow Baltic Sea. The Type 205 is a direct evolution of the Type 201 class with lengthened hull, new machinery and sensors. The biggest difference though is that ST-52 steel is used for the pressure hull since the Type 201's non-magnetic steel proved to be problematic. Type 206, the follow-on class, finally succeeded with non-magnetic steel hulls.