Trondheim, Norway: Kristiansten fortress

Trondheim had a problem in the late 1600s. Its traditional military defenses were along the river, but that left the city vulnerable to an attack from the east ... and, oh by the way, Sweden was east of Norway. Up went the Kristiansten fortress to add a little security to the situation.

The Swedes didn't think this would be a problem when they invaded in 1718. But the Norwegians put up quite a fight, and held off the opposition until winter set in. It was time for Sweden to retreat, but the weather was not on their side. Their retreat left many of the soldiers dead along the way in a military action that later drew comparisons to Napoleon's retreat from Russia. 

The fortress got out of the military business in 1816. It became a fire watch, thanks to a good location on top of a hill. Then in 1997, the facility hosted a museum. Meanwhile, the Germans executed a number of Norwegians here during their occupation in World War II. Norway returned the favor when it executed nine traitors on the same piece of land. 

These days, it seems that tourist buses come visiting for the view. It's a good one.