Akershus festning

Akershus festning, 0015 Oslo

The old fortress and castle on a rise by the fjord are free to wander, with ramparts, cannons, cobblestones and uniformed guards. The lawns are big enough to run on, and from the ramparts you look out over the harbour.

Entry to the fortress grounds themselves is free. If you want to go into the museums, you can buy a combined ticket covering the Armed Forces Museum, Norway's Resistance Museum and the other museums on the site. The fortress was originally built in the late 1200s.