Hot Hole is a geothermal hot spring within Elko, Nevada.  A high fence surrounds the pool of water, which remains a constant 133*F.  The site has been known since the days of the California Trail, along w/ nearby Elko Hot Springs.  A historical marker reads the following:

California Trail - Hot Springs

"We reached the "hot springs".  They are situate on the left side of the river... on its immediate bank... there was a large lake immediately over the bluffs, the waters of which were equally as hot."  Amos Steck, Aug 20, 1849