Switzerland does have one claim to fame that no other country can boast, they can put their whole population in underground nuclear bunkers if needed. A bunker is a military or civilian shelter that is partly buried, or in some cases completely buried. Generally, they are hidden in the landscape and designed to keep citizens safe from attacks such as falling bombs.
The Swiss military has very strong historical links to using the landscape to their advantage. Which is why the bunkers are an integral part of their strategy, they are the most popular defense military system in Switzerland. According to history, the first major bunker was built in 1886 and 1937, with the ever-growing threat of a great war coming up, General Henri Guisan oversaw the construction of many bunkers throughout the Swiss Alps.
It is thought that by the end of World War II in 1945, Switzerland had spent over 10 billion dollars on bunkers! And then in 1963, the government decided they would ensure there were enough bunkers to provide every single citizen shelter in the case of an atomic attack. This means that Switzerland is the only country in the world that has built enough space underground to protect its whole population there is even space left over.
By 1995 the department of defense in Switzerland owned over 20,000 defense objects and 11000 buildings. This meant that the DDPS was the biggest building owner in the whole of Switzerland. There are over thousands of bunkers on Swiss soil spread all over the country.
Occasionally some of the secret bunkers are opened up the public, one of the bunkers named K20 is reserved for the swiss government and is located near the city of Kandersteg. As the bunkers have never been needed, some are being repurposed in stages of demilitarization, this means you find military bunkers and fortresses being used as a commercial use or even as private homes.