Samara, known as Kuybyshev during Soviet times, is a 1+ million cityon the Volga about 600 miles southeast of Russia. And yes, Stalin's bunker was situated in Samara- indeed, the city was the country's secondary capital from 1941-43. Because the city was involved in aerospace manufacturing (including space flight), it was a 'closed city' during the cold war.
192 stairs lead to the mine 8 m in diameter. There are studies, living rooms, service and economic rooms in the bunker. There is no other such an outstanding building in the world as this one. It was built from March till December in 1942.