Black Canyon of the Colorado the Nevada side of the canyon is the Sauna Cave. This cave was drilled by miners working on Hoover Dam while it was being constructed. It is a deep cave with calcium carbonate crystals on the walls. At the end of the cave is a hot spring, which causes temperatures in the cave to reach . One prominent canyon that splits from this canyon south of the Hoover Dam is Boy Scout Canyon. Boy Scout Canyon has water running through it that is warmed from a geothermal source. On the Arizona side of the river, there are several large hot
Steamboats of the Colorado River Quartette Landing and Eldorado Canyon in Nevada, the landings and the mills there were abandoned. The town of Nelson was founded near the head of the canyon nearest the road to the railroad, the post office of Eldorado was closed in August 31, 1907 and moved to Nelson. In 1906, Santa Fé railroad built the Barnwell and Searchlight Railway to the west to tie Searchlight to its subsidiary California Eastern Railway at Barnwell, California. Also in 1905, the Arizona and California Railroad bridged the Colorado River at Parker, Arizona, cutting in half the last profitable section of the river for