15 Hidden Facilities Inside Mountains

15 Hidden Facilities Inside Mountains

Mountains have long been humanity’s favorite hiding place—impenetrable natural fortresses where secrets can be buried in rock and ice. From clandestine command centers tunneled beneath alpine peaks to entire research complexes shielded by thousands of feet of granite, some of the world’s most vital—and mysterious—installations operate out of sight, deep within these rugged landscapes. In the countdown ahead, we’ll uncover fifteen real facilities built inside mountains, explaining why they were created, how engineers overcame immense geological challenges, and what still remains behind those locked blast doors today. Credit to : Top Fives