I stumbled across some interesting facts on fallout shelters (emphasis added):
The former Soviet Union and other Eastern Bloc countries often designed their underground mass-transit and subway tunnels to serve as bomb and fallout shelters in the event of an attack. Currently, the deepest subway line in the world is situated in St Petersburg in Russia, with an average depth of 60 meters, while the deepest subway station is Arsenalna in Kyiv, at 105.5 meters.[14]
Germany has protected shelters for 3% of its population, Austria for 30%, Finland for 70%, Sweden for 81%,[15] and Switzerland for 114%.
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Switzerland built an extensive network of fallout shelters, not only through extra hardening of government buildings such as schools, but also through a building regulation requiring nuclear shelters in residential buildings since the 1960s (the first legal basis in this sense dates from 4 October 1963).[24] Later, the law ensured that all residential buildings built after 1978 contained a nuclear shelter able to withstand a blast from a 12-megaton explosion at a distance of 700 metres.
Those Swiss! See also: