San Juan Mountains

The San Juan Mountains are a rugged mountain range 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. Mining is now uneconomical in the region, the last holdouts being 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.

There is some tourism in the region, with the narrow gauge railway between Durango and Silverton being an attraction in the summer. Jeeping is popular on the old trails which linked the historic mining camps, particularly thrilling is the Black Bear Road. Visiting old ghost towns is popular as is wilderness treking and mountain climbing. The San Juans are extremely steep, only Telluride has made the transition to ski resort. Purgatory is a small ski area north of Durango near the Tamarron Resort. There is also sking on Wolf Creek Pass, an area used mostly by locals.

The Rio Grande rises on the east side of the range. Rivers on the west side of the continental divide are tributaries of the Colorado River.