The Karlskrona naval base (Swedish: Karlskrona örlogsbas) is the largest naval base of the Swedish Navy. Located in Blekinge in southern Sweden, the base has close ties with the city of Karlskrona. It has an exceptionally well-sheltered location: arcs of islands provide a strong defense not only from the sea but also from land attacks. Two of Sweden's three naval warfare flotillas are based there. It contains the Marinmuseum and the Ropewalk, the longest wooden building in the country.