The project was under construction for 17 years, and the construction was nearly completed in 1984. In 1964 China made its first public nuclear test. Largely due to change in the Cold War international situation, the project was cancelled in February 1984.[2] It was further declassified in April 2002.[2] In April 2010, after being closed for over 25 years, the base was opened to tourists.[1][2]
Structure
The surface area of the cave is more than 104,000 m2, and the total length of the tunnels is more than 20 kilometers.[3] The whole complex consists of 13 levels, 18 artificial caves linked to each other, and has more than 80 roads and 130 tunnels.[3]Automobiles are able to pass the roads and tunnels inside.[3] The base has the “World's Largest Artificial Cave”,[1] which has a height of 79.6 meters, roughly equal to that of a 20-floor building.[3]