Hammershus, situated on the northern tip of Bornholm (called Hammeren), is Northern Europe’s largest medieval castle/fortification. The ruins are situated 74 meters (243 ft) above the Baltic Sea. Historians think the castle was built at the beginning of the 13th century as a royal residence for Vlademar II of Denmark and a base for the Danish crusades.
The fortification consists of the base castle residence and accompanying Mantel Tower, and includes a great stonewall stretching 750 metres (2,460 ft) around the castle grounds.
Hammershus has a long history of power struggles, taken by Lübeck in 1521, Sweden in 1648, and recaptured by Denmark that same year. In addition to power struggles, Hammershus also served as a prison on several occasions. Hammeren, one of the highest points on Bornholm, offers stunning views of the Baltic Sea.