Magletsch

Magletsch is a former rock-hewn artillery fort above the village of Gretschins, in the municipality of Wartau, canton of St. Gallen. Known under the military codename A 6020 "Der Hammer," it spent decades as one of the Swiss Army's most closely guarded secrets — today part of its tunnels can be visited as a museum, and the surrounding cliffs draw climbers.

Why was a fort built here?

Construction began in 1940, at the height of Switzerland's mobilization against the threat of war. Magletsch formed the northeastern corner of the large Sargans defensive complex, one of the pillars of the so-called National Redoubt — a strategy of anchoring national defense in fortified mountain massifs. The garrison's job was to control the Rhine valley above the fortress and the approaches toward Wildhaus and Feldkirch, key corridors leading into the Alps.

The fort held seven cannons, making it one of the largest and most powerful artillery works in the entire Redoubt. Building it required enormous resources — the project is estimated to have cost around 13 million Swiss francs of the time, a striking sum given the mountainous, underground setting.

What is hidden underground?

Inside Magletsch runs a tunnel network roughly 3.8 kilometers long. Because the local rock is permeable to water, every gallery had to be fully lined in concrete, or the installations would have suffered constant dampness. The complex was designed as a self-sufficient base for 381 soldiers, complete with its own bakery, laundry, and a 70-bed field hospital.

Power came from three 200-horsepower Sulzer diesel engines, fed by two tanks holding 100,000 liters of fuel each. Drinking water was supplied from two reservoirs with a combined capacity of 1.6 million liters, while a powerful ventilation system kept air quality in the tunnels breathable despite the absence of natural airflow.

What does the fort look like today?

The 1995 Swiss Army reform ended Magletsch's active combat role. Since 2000, part of the fortress has been open to visitors as a fortification museum — the Artillerie-Fort Magletsch (AFOM) — run by a local association of military history enthusiasts. The visit covers both the technical backbone of the fort and the everyday conditions its garrison lived under.

Above ground, the earthen cover that once camouflaged the fort has become a valuable habitat for rare flowers and plants, and a dedicated nature conservation plan now protects the site. The rock faces around Magletsch also serve as a climbing area (Klettergarten), popular with climbers from the Sarganserland region.

How to get there and when to visit?

Magletsch lies in the municipality of Wartau, in the Werdenberg region, close to the villages of Gretschins and Oberschan, in the canton of St. Gallen. The region sits at the eastern edge of Switzerland, near the borders with Liechtenstein and Austria, so the easiest approach is by car or by train to one of the Werdenberg towns, followed by local transport or a short walk.

Museum visits typically run as guided tours, so it is worth checking the current schedule before setting out, since the fort is not open every day. The best time to visit is spring through autumn, when the surrounding hiking trails and climbing area are also accessible; in winter, snow can make reaching the entrances harder.

Frequently asked questions

What is Magletsch? It is a former underground Swiss Army artillery fort built in 1940, part of the Sargans fortress system, now partly open as a museum.

Why was the fort nicknamed "Der Hammer"? The military codename reflected its firepower — with seven cannons, it ranked among the largest artillery works of the National Redoubt.

Can visitors go inside the fort? Yes, since 2000 part of the complex has operated as a museum (AFOM), showing the tunnels, technical installations, and the living conditions of the former garrison.

Are there other activities nearby? Yes, the cliffs around Magletsch form a well-known climbing area, and the hill covering the fort is now a protected habitat for rare plant life.