Artilleriewerk Halsegg

The Artilleriewerk Halsegg consists of two identical single-block bunkers built into the mountainside at 1340 meters (4400 feet) on Alp Halsegg near Sattel. Both structures are embedded in solid rock and contain military equipment, storage facilities, and exhibition spaces.

Built between 1986 and 1988, this fortress served as a test model for the BISON defense concept and was designed to protect the Seedamm region from potential attacks from the north. The project was part of Switzerland's Cold War defense planning.

The second bunker now houses a museum dedicated to Guillaume-Henri Dufour, where visitors can see displays about his work in military strategy, engineering, and mapping. This space shows how his innovations shaped Switzerland's development.

The site opens for visits mainly on weekends and by prior arrangement, allowing visitors to explore the original military equipment in guided groups. Reaching it requires a mountain hike, so appropriate footwear and a reasonable level of fitness are helpful.

One bunker retains its original setup with two 10.5 cm cannons on rotating mounts that are still visible and functional today. This first bunker can also accommodate up to 24 people for overnight stays, offering an unusual experience of sleeping inside an actual fortification.