25. Kastellet Fortress, Copenhagen
The Kastellet in Copenhagen is considered as one of the best preserved fortresses in Europe. It is a Citadel with magnificent views, where a number of buildings can be found within. There is a church as well as a windmill and it also hosts a lot of military activities although it is mainly a park that is open to the public. This historic site is located in Copenhagen, Denmark and is a must see if you happen to visit Denmark in one of your European trips.
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