Mitholz

[4] More than 7,000 tonnes of munitions, including aerial bombs, artillery rounds, land mines and hand grenades, were stored by the Swiss Armed Forces in a depot inside a mountain overlooking Mitholz.

The depot, one of the largest in a system of underground weapons stores built during World War II as an expansion of the National Redoubt, consisted of 6 chambers 150 metres (490 ft) in length.

Forty buildings in the village, including the station and the school, were destroyed by flying rocks and fire from exploding ordnance; nine people were killed, four of them children, and 20 injured.

[6] In 2018, the Federal Department of Defence, Civil Protection and Sport announced that approximately half the munitions had not exploded, but remained inside the collapsed depot and under unstable rock, and a commissioned safety study found that there was a risk of another explosion.

[4] In February 2020, a further announcement was made that the village must be evacuated by 2030 in order for the Armed Forces to either remove or safely bury the remaining munitions, which is estimated to require ten years.