The Kryle-Ringelnatter fortress, which is located 3.8 km north of Søndervig, was part of the Atlantic Wall and was established in 1943-1944. The entire fortress consists of 50 bunkers and there were originally 50 other concrete and wooden structures at the site. Moreover, mine fields and barbed wire surrounded this large fortress.
The northern part of the fortress was called the Kryle-position, which was a coastal military artillery installation with many bunkers and canons. The southern part of the fortress, called Ringelnatter, belonged to the Luftwaffe; this structure featured radar equipment, canons, and wooden baracks. The canons that were positioned there were old and not very effectful, so that part of the fortress was an illusion designed to make people think that the whole coast line was defended.
There are many single bunkers throughout the area but from Houvig Strand's parking lot, which is located 3.8 km north of Søndervig, there are an anti-aircraft-artillery, concrete foundations for radar, machinegun pits, bunkers for troops, and a splitter-bunker, which is a brick wall for the protection of wooden baracks against shell fragments.