The Fredriksten Fortress, a famous Norwegian historical monument, was built in compliance with an express royal order. It took 40 years to build the fortress, with the construction work starting in 1661 and ending in 1701.
The idea behind the fortress was to reinforce security at the volatile Swedish-Norwegian border. The fortress is located in Halden, a Norwegian border town that neighbors Sweden. The once battle fortress is now a memorial to Scandinavian military operations.