Gävle is an important port about 175km north of Stockholm. In the Cold War, its approaches were protected by three underground coastal artillery forts. Two of these were to the north of the harbour approaches, in Gråberget,
The third fort is open to the public and is located to the south, near the settlement of Furuvik. It is located on an island and accessed through an amusement park and zoo. The fort was equipped with 75mm cannon; construction started in 1957 and the site closed in 1984. There was also a large searchlight (still extant) and anti-aircraft guns as part of the port’s defences.