Archaeologists discovered an exceptionally large medieval shipwreck off the Danish coast during a seabed survey for Copenhagen. The wreck, dubbed Svaelget 2, is a 14th-century cog merchant ship. Tree-ring analysis dates its construction to around 1410 CE. It lay half-buried in sand 12 meters deep in the Øresund strait, offering a rare, well-preserved find.

Measuring about 28 meters long and 9 meters wide, this cog could carry roughly 300 tons of cargo—far larger than typical vessels of its era. Its timber was sourced from the Netherlands and Poland, reflecting extensive medieval trade networks. The ship's size suggests a wealthy merchant class investing in ambitious voyages to move goods across the Baltic Sea.

Remarkably, the wreck's starboard side remained intact, preserving upper structures like the stern castle. Most cogs erode away, leaving only their hulls. This find provides the first physical evidence of how these castles were built and connected, moving beyond historical drawings and descriptions of these innovative trading ships.