Ertholmene is a small, rocky archipelago located in the Baltic Sea near Bornholm. Only two of the six islands are inhabited. Tourists can get there on a yacht or a small cruise ship. The Ertholm ferry operates between Christiansø – the largest island of the archipelago, and Gudhjem and Allinge. It was built in the German shipyard in 1967 and 294 passengers can be boarded. The ferry travels at the speed of thirteen knots. Before each season the Ertholm undergoes a technical inspection in Nexø.