(Image: via China Daily; 816 Nuclear Military Plant)
For years, the 816 Nuclear Military Plant was one of China’s most closely guarded secrets. That all changed in 2002, though, when the underground nuclear base in Chongqing was declassified by the Commission of Science, Technology and Industry for National Defence. It’s now open to visitors.
The project, which was designed to reinforce China’s defensive network in the face of increasing tensions with the Soviet Union, was launched 1966. But building the top secret underground base, which is located in Southwest China, was a massive undertaking. Working under a veil of intense secrecy, construction workers carved out the largest artificial cave in the world, in an epic feat that employed more than 60,000 people.
With more than 20 kilometres of tunnels, 18 individual caves, and a height that would allow a 20-story building to be constructed inside, 816 Nuclear Military Plant took 17 long years to build. It was designed to withstand 8-magnitude earthquakes and explosions equivalent to those generated by thousands of tons of TNT.
The project was halted in 1984, called off because of the relatively peaceful environment that China found itself in at the time. Even then, 816 Nuclear Military Plant remained classified for decades after. The secret nuclear facility’s existence was considered so sensitive that even after it was decommissioned, many locals remained unaware of its existence near their homes.
China Daily reported in 2010 that the once-classified nuclear warfare tunnels of 816 Nuclear Military Plant would be opened to the public in stages, as resources allowed. Dong Guanzhi, a Jinan University professor who worked as a consultant on the project, described the cave “magical, mysterious and holy”, and hoped that it would offer people a glimpse at China’s true military history.