Kastellet is one of the few surviving star-shaped fortresses in Northern Europe. The citadel was founded in the 17th century by the Danish king Christian IV, and, most interestingly, it still belongs to the Danish Ministry of Defense. The offices of the army general staff, military intelligence and the military prosecutor's office are located here. Despite such a serious administrative burden, the territory of Kastellet is freely accessible to everyone. In the fortress, you can see the warehouse buildings, gunpowder storage, the building of the church and prison, as well as a cute windmill.→