Underground base

An underground base is a subterranean facility used for military or scientific purposes.

Examples are:

There may be more than 10,000 underground military facilities worldwide.

See also

References

  1. ↑ Richelson, Jeffrey T. "U.S. Intelligence: Hiding of Military Assets by "Rogue Nations" and Other States a Major Security Challenge for 21st Century". gwu.edu. George Washington University. Retrieved 16 July 2020.