Bohus Fortress built
1308 CE.
Shown on the map at 57.862°, 11.999°.
Bohus Fortress lies in Kungälv, Bohuslän, Sweden, north east from Hisingen where the Göta river splits into two branches (20 km (12 mi) north of Gothenburg). It commands the surrounding area from a cliff 40 m (130 ft) high, with the river forming a natural moat around it. The fortress used to be situated along the old Norwegian–Swedish border.
Text from the Wikipedia article Bohus Fortress, licensed CC BY-SA 4.0.