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It might pass for the lair of a James Bond supervillan but this former nuclear bunker is perhaps the world's most outlandish datacenter.
This co-location facility for Swedish internet service provider Bahnhof lies 100 feet below Stockholm, and is decked out with tropical plants, a waterfall, 600-plus gallon fish tank and craggy granite walls.
The servers are located in four caves, radiating from the centre of the bunker.
Building work on the bunker began in 1943, and the shelter was extended during the Cold War to become a civil defence bunker stocked with provisions and emergency vehicles.
The site's other claim to fame is hosting two servers for the Wikileaks whistleblower website.