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 Colorado route, and was the model for all the steamboats on the river thereafter. From 1859, prospectors dispersed up the Colorado River valley in the next few years, finding gold deposits along the river as far as the Black Canyon. In 1860, gold was found across the Colorado River from Potholes in Arizona, in placers at La Laguna. The strikes that followed in the next four years would make George A. Johnson and his two partners wealthy. By March 1861, the secession crisis had led to the closing of the Butterfield Overland Mail. February 19, 1861, the Bascom Affair led