The San Juans
The San Juan Mountains are a rugged mountain range in the Rocky Mountains in southwestern Colorado. The area is highly mineralized (the Colorado Mineral Belt) and figured in the gold and silver mining industry of early Colorado. Major towns, all old mining camps, include Creede, Lake City, Silverton, Ouray, and Telluride. Large scale mining is now uneconomical in the region, although independent prospectors still work claims throughout the range. The last large scale holdouts were the Standard Metals operation on Red Mountain Pass which operated until late in the 20th century and the ill-fated Summitville mine on the eastern slope of the San Juans.
The Summitville mine was the scene of a major environmental disaster in the 1990s when the hastily installed liner of a cyanide-laced tailing pond began leaking heavily. Summitville is in the Summitville caldera one of many extinct volcanoes making up the San Juan Volcanic Field. One, the La Garita Caldera, is 35 miles in diameter. Large beds of lava, some extending under the floor of the San Luis Valley, are characteristic of the eastern slope of the San Juans.
