Akershus Castle is a medieval castle located in Oslo, the capital of Norway. The Akershus Fortress was constructed in the late 1290s by King Håkon V to defend against attacks from the Norwegian nobleman, Earl Alv Erlingsson of Sarpsborg. The fortress’s value came from its planned location near the sea, and it has survived copious sieges, never being captured in active battle. The Akershus citadel has the status of a national symbol because of its role as seat of the king and government and the many important and remarkable historical events that have taken place here. The national significance is underlined by the fact that the fortress now used as government's premier entertainment venues and hosts the Royal Mausoleum.