This is Pionen White Mountains, the nuclear bunker in which Wikileaks will locate some of its servers. It was excavated 98 feet underground, in a rock hill in the center of Stockholm, Sweden, during the Cold War.
Originally, it was just a bomb shelter built in 1943. In the 70s, the Swedes turned the shelter into a full bunker, a civil defense center that was going to hold an emergency unit of the Swedish government in the case of a nuclear war.
Now, protected under thirty meters of rock and 1.64-feet-thick solid steel doors, it is the colocation center of Bahnhof, a Swedish internet hosting company. Bahnhof expanded the facilities, blasting new space for gas oil power plants extracted from decommissioned German submarines. In the case of an external power outage, the generators would kick in, keeping the servers running non-stop.
It also looks like they hired the same interior designer who decorated Batman's lair:
Apparently, the Bahnhof people are pretty happy to host Wikileaks in their ultra-secure bunker, safe from any political pressure and physical assaults. Wikileaks is under attack by the US government for the publications of many of its secrets. Most recently, Wikileaks released 100,000 internal military documents from the Afghanistan war.