The Granite Mountain Vault lies hidden away on the north face of Little Cottonwood Canyon in Salt Lake City. Built by the Church in the early 1960s, the Vault lies under 700 feet of stone, and was meant to withstand a nuclear blast. Contrary to the ramblings of your crazy uncle, it safeguards mainly genealogical microfilm. There is an manmade lake inside that keeps humidity at the optimal level. Alas, it is no longer open for public tours.