Close to the Galgberget one can see an entrance leading underground, to a bunker or something like that. People believe the place to be everything from a bomb shelter to underground hospital drug supply, but it is in fact an old command center for civil defense. It was built in the 1950s and called Apan (“The monkey” in Swedish). Up to 70 people could live and work down there. The underground house has two floors, and includes sleeping accommodation, as well as dining and working facilities. In the heart of it lies a command room from which the civil defense could keep track of what happened off the mountain in the event of war or attack. There you could sit and watch if any aircrafts or ships were approaching the island. 

The place has never been used in a real danger situation, but over the years a large number of exercises and training have been held here, both for the civil defense and rescue services.