Subterranean river in Castellet-lès-Sausses

Subterranea are underground structures, both natural (such as caves) and human-made (such as mines).[1] Some subterranea and related topics include:

Natural

Human-made or related

See also

References

  1. ^ Margineanu, Romul Mircea (2019). "Radon measurements in underground mines and caves from several European countries". AIP Conference Proceedings. Author(s). 2076: 050004. doi:10.1063/1.5091643.