When WikiLeaks wants to safeguard its trove of diplomatic cables or Kraft needs to keep tons of cheese cold, they head beneath the surface.

Pionen Data Center Stockholm, Sweden Where does WikiLeaks keep its secrets? In a former military bunker and nuclear shelter under Stockholm’s city streets. Nicknamed the James Bond Villain Data Center, this 8,000-server facility, which could theoretically withstand a nuclear impact, is protected by 24-hour video surveillance and a 2-foot-thick armored door. Two German V12 diesel submarine engines are on standby for backup power. Recycling a war room comes at a price, though: Bahnhof—the ISP that runs the data center—had to have the glass and frames for the walkway and conference room custom-cut to accommodate the curved walls and uneven ceiling.

Photos: Christoph Morlinghaus

Chapel of St. Kinga Wieliczka Salt Mine Wieliczka, Poland Before going down into the dark, many miners pray. (So would you.) It’s not uncommon for them to build chapels in the caverns they create, and the workers in this Polish salt mine took that task seriously, carving a 10,400-square-foot chapel into the crystalline walls. Józef Markowski started work on this particular chamber in 1896, handing it off to his brother Tomasz in 1920. Nearly everything in the room—from the chandeliers to the bas-reliefs—is carved out of rock salt. Wieliczka, which was a working mine from the 13th century until 1996, holds some 2,000 excavation chambers on nine underground levels, many decorated by miners with carvings and chapels dedicated to saints—and to those who lost their lives digging sodium chloride out of the earth.

Kraft Foods Distribution Center Springfield Underground Springfield, Missouri Nearly every ounce of Kraft cheese product—from Velveeta to Kraft Singles—spends part of its life in a 680-pound container inside this 400,000-square-foot subterranean fridge. It’s not about aging, it’s about cheap storage: Moving refrigeration underground saves massive amounts of energy, since the temperature 100 feet down is a constant 58 degrees Fahrenheit. An aboveground pump sends 13,000 gallons of chilled brine through the system every day, keeping the warehouse at a cool 36 degrees. The Kraft facility is actually part of a massive complex that started as a limestone mine in 1946. (The mine is still operational, but a substantial earthen buffer shields the employees of Kraft and other companies from regular explosions.)

Dinorwig Power Station (aka Electric Mountain) Gwynedd, Wales When millions of British football fans flip on their electric kettles at halftime, Dinorwig’s hydropower operation kicks into action to handle the spike in demand: 10 million cubic meters of water in a reservoir on the surface rush down a network of pipes to drive six turbines located 300 feet below the surface. The hall that holds the turbines—a former slate mine and Europe’s largest man-made cavern—lies deep below Elidir Mountain. Dinorwig can generate 1,320 megawatts in just 10 seconds, making it the zippiest power generator in the world.