Sperrstelle Bözberg, Military fortification museum at Bözberg Pass, Switzerland

Sperrstelle Bözberg is a Swiss Army barrier of the Tafeljura, spread over the Bözberg plateau and around the Bözberg Pass as part of Border Brigade 5. Its Eichwald group near Oberzeihen, built in 1940, holds twelve infantry bunkers of varied design, protected by anti-tank walls, dragon's teeth and rail obstacles. The bunker Sagemülitäli A 3951 is a two-storey structure with caverns and a natural rock gallery, its fire aimed at a tank barrier whose remains lie ten metres below in the stream bed.

The Swiss Army constructed this fortification between 1936 and 1940 as part of the fourth defense line behind the Rhine during World War II. It was designed to serve as a strategic barrier against potential threats from the north.

The command post of Border Brigade 5 at Balmhübel in Wallbach was bought in 2016 by the association running the Military and Fortress Museum Full-Reuenthal, which now looks after it. Its command wing holds a wall painting, the «Kartoffelanbauschlacht» by René Villiger. The brigade telephone switchboard there was shut down in 2014.

The works lie scattered across the Tafeljura around the Bözberg pass and near Oberzeihen, Effingen and Villnachern, mostly on the Eichwald army shooting range, so many bunkers can only be reached on foot. The infantry bunker Sagemülitäli A 3951 in the Sagemülital (Linn) is a two-storey structure with caverns and a natural tunnel; the remains of its anti-tank barrier are visible in the stream bed 10 metres below. The artillery bunker Stelli Nord A 3925 keeps a restored 8.4-cm Krupp field gun from 1879 on a pivot mount, reached by stairs and a tunnel from the rear slope.

The command post features a wall painting depicting agricultural scenes, symbolizing the connection between soldiers and the local population. This unexpected detail shows how deeply the region's daily life was woven into military planning.