This is a part of one of two main tunnels of the "Government Bunker Germany" ( German: "Regierungsbunker" ), officially named "Ausweichsitz der Verfassungsorgane des Bundes im Krisen- und Verteidigungsfall zur Wahrung von deren Funktionstüchtigkeit (AdVB)", ( English: "Emergency Seat of the Federal Constitutional Organs for the State of Crisis or State of Defence to Maintain their Ability to Function" ), near Marienthal, Ahrtal, Germany.
NATO mandated Germany to provide for a fallback of the government in case of war. In the case of a nuclear strike, the government had to coordinate the counter-strike with NATO from here. It was build from 1960 to 1972.
But there were some problems. At the time of its completion, the bunker had been overtaken by the possibilities of weapon technology. It could only withstand the power of a Hiroshima bomb at 1km / 0.62mi distance - 13-20 Kilotons TNT. But nuclear weapons of the 80's reached the power of 8-10 megatons. And the supplies lasted for 30 days. No one thought about Day 31 ... the assumption was that a nuclear stroke treatment was finished after about 14 days.
The two main tunnels, never used old railway tunnels, are together 3 km / 1,86 mi long. In addition, another 14 km / 8.7 mi side tunnels were driven into the rocks. He offered space for 3000 servants. Family members or spouses were not allowed to enter in an emergency.
Although the end of the Cold War coincided with the fall of the Berlin Wall, the operation of the bunker continued unchanged. In Mai 1997 the heavy Diesel-power-Generators were renewed. The decision to give up the "Regierungsbunker" lastet until 7 December 1997. 7 years after the end of the Cold War.
Normally bunkers are only closed. But in the early 00's, this one was dismantled and gutted within 4 years with German thoroughness, except on September, 11th 2001...
Today all tunnels are absoluteley empty. Except 203 m / 222 yd / 666 ft. This part of the government bunker has been preserved for visitors. You should take a look when you are in this area of Gemrany. https://goo.gl/maps/d4FGiNVn9292 | Dokumentationsstätte Regierungsbunker
Am Silberberg 0, 53474 Bad Neuenahr-Ahrweiler, https://regbu.de