This fortress was built in 1810, and in use until 1835. Since that it was left and gradually fell apart over the decades. German occupation during WW2 left it in ruins. Enthusiasts started restoring it in 1994, and it's now completely renovated, using the original plans and drawings by the first architect (Friis). The fortress is now a popular recreational area for the citizens, with open air concerts during the summer, and it's own regiment of grenaders.