Underground data centers seem like they only belong in movies. However, here's real one that is complete with greenhouses, waterfalls, German submarine engines, simulated daylight and can withstand a hit from a hydrogen bomb. It looks like something out of a super hero or spy themed flick. It is a security center that is run by one of Sweden's largest ISPs. It is newly opened and positioned deep below the bedrock of Stockholm city, in an abandoned nuclear bunker. It is completely shut off from the world with the help of entrance doors that are 16 inches thick. Check out the pictures of it. I assure you it is real and not a set from one of the Bond movies.

Things you should know about the data center

* Originally a nuclear bunker: The data center is housed in what was originally a military bunker and nuclear shelter during the Cold War era. The facility still has the code name from its military days: Pionen White Mountains.
* Located in central Stockholm below 30 meters (almost 100 ft) of bedrock: The facility has 1110 sqm (11950 sq ft) of space and is located below 30 meters of solid bedrock (granite) right inside the city.
* Fully redesigned in 2007-2008: Pionen was completely redesigned in 2007-2008 to become the data center that it is today. More than 4,000 cubic meters (141,300 cubic ft) of solid rock was blasted away to make more room.
* Can withstand a hydrogen bomb: The bunker was designed to be able to withstand a near hit by a hydrogen bomb.
* Houses the Network Operations Center for one of Sweden's largest ISPs: The bunker houses the NOC for all of Bahnhof's operations. They have five data centers in Sweden, Pionen being the largest. The facility also acts as a co-location hosting center, so you can actually put your own servers here.
* German submarine engines for backup power: Backup power is handled by two Maybach MTU diesel engines producing 1.5 Megawatt of power. The engines were originally designed for submarines, and just for fun the people at Pionen have also installed the warning system (sound horns) from the original German submarine.
* 1.5 megawatt of cooling for the servers: Cooling is handled by Baltimore Aircoil fans producing a cooling effect of 1.5 megawatt, enough for several hundred rack-mounted units.
* Triple redundancy Internet backbone access: The network has full redundancy with both fiber optics and extra copper lines with three different physical ways into the mountain. Pionen is one the best-connected places in northern Europe.
* Work environment with simulated daylight and greenhouses: For a pleasant working environment the data center has simulated daylight, greenhouses, waterfalls and a huge 2600-liter salt water fish tank.
* Staff: 15 employees, only senior technical staff, work full time in Pionen.

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