Boden Fortress built
1908 CE.
Shown on the map at 65.791°, 21.657°.
Boden Fortress (Swedish: Bodens fästning) is a modern fortress consisting of several major and minor forts and fortifications surrounding the city of Boden, Norrbotten, in northern Sweden. The fortress was originally intended to stop or delay attacks from the east or coastal assaults, which at the time of construction meant Russian attacks launched from Finland. It was primarily the expansion of the railway network in Norrland, which in turn was a consequence of the rising importance of the northern iron ore fields, that led to the increased strategic value of northern Sweden and the construction of the fortress. Although the main forts were finished in 1908, many of the supporting fortifications were not completed until the start of the First World War. Improvements were also continuously made during, and between, both World Wars. Boden Fortress is made up of five primary self-supporting forts excavated out of the bedrock in five of the mountains surrounding Boden: Degerberget, Mjösjöberget, Gammelängsberget, Södra Åberget and Rödberget.
Text from the Wikipedia article Boden Fortress, licensed CC BY-SA 4.0.