Fjell Fortress has several bunkers with interesting stories. A lot of the bunkers belonging to the fortress are unique, not just in Norway, but also in a European context
You can download the app to your mobile phone locally. This means you can use the app in the field without using data. Download the app before you visit, if you want to use the app while visiting the museum.
Download the app www.digitalfestning.no for free and find out more about the area surrounding you.