The mystery ship: København was a Danish, British-built five-masted barque used as a naval training vessel until its disappearance after December 22, 1928.
Built for the Danish East Asiatic Company in 1921, it was the world's largest sailing ship at the time, and primarily served for sail training of young cadets.
The København was last heard from on December 21, 1928, while en route from Buenos Aires to Australia. When it became clear the ship was missing, a lengthy search ensued, but neither København nor anyone who had been aboard her on her final voyage was ever found. Despite both the extensive search and much speculation about the vessel's fate, København remains missing and what happened to her crew and cadets remains a mystery.
In April 1929, four months after København was last seen and heard from, the Danish East Asiatic Company dispatched a motor vessel, the Mexico, to Tristan da Cunha. Residents reported having seen a large five-masted ship with its foremast broken on January 21, 1929; however, it had not attempted to land on the island. The Mexico, joined by the British Royal Navy, searched for the København for several months, but found no sign of it. The Danish government officially declared the ship and its crew were lost at sea.
Source: Erick Navas