Oscarsborg fortress - cannons and fortifications

Tired of doing the tourist circuit in Oslo? Just 30km south lies Oskarsborg fortress, a decommissioned military fortress guarding the entrance to the inner Oslo fjord where the fjord is at it’s tightest. In 1905, the Oscarsborg fortress was regarded as the strongest fortress in northern Europe, with a defensive line that stretched 10 km out the Drøbak sound. The fortress is open to the public year round, has some shops and restaurants, and a harbor for leisure craft. Explore the tunneled fortifications and huge 28cm cannons that where used in anger at the beginning of the Second World War to sink the invading German heavy battlecruiser Blücher as it attempted to take Oslo and capture King Håkon 7th. After a barrage of cannon fire and torpedos, the ship glided for approximately  two kilometers before sinking to the north of the island. 800-1000 lives where lost as soldiers escaped in to the wintertime ocean. Blücher still lies there today. A museum in the fortress gives more background. While you are there, take time to climb the wooden watchtower in the middle of the island to watch shipping and a great view. To the south of the island you can spot an underwater fortification that forces all but the smallest boats to pass the island on the east. If you walk up the norteast side of the island you will also find the enterance to an underwater torpedo battery with a huge torpedo on exhibit outside. Finally at the north western end you can enjoy a swim from the commandant’s bath house on a warm summer day.