Mount Jefferson Wilderness
The Mount Jefferson Wilderness is a wilderness area located on and around Mount Jefferson in the central Cascade Range of Oregon in the United States. The wilderness lies within the Willamette National Forest and Deschutes National Forest. The wilderness area covers, with more than 150 lakes. It also has of trails, including of the Pacific Crest National Scenic Trail. Three Fingered Jack and Mount Jefferson are both prominent features of the wilderness area. Mount Jefferson Wilderness is the second most visited Oregon wilderness area after the Three Sisters Wilderness.
Geography
At, Mount Jefferson is the second tallest mountain in Oregon. It is a stratovolcano with slopes mantled by five glaciers - Whitewater, Waldo, Milk Creek, Russell, and Jefferson Park. Three Fingered Jack is a heavily eroded and deeply glaciated shield volcano and consists mainly of basaltic andesite lava. At, it is made up of the solidified lava plug flanked by ridges of the old volcano's subsidiary lava dikes and lies at the southern end of the Mount Jefferson Wilderness. Other geographic features of the wilderness include steep talus slopes, rock outcrops, and alpine meadows.Several lakes are situated within the wilderness area, including Marion Lake, Duffy Lake, Santiam Lake and Wasco Lake. Between Three Fingered Jack and the North Sister volcano and among recently active basalt lava fields, there is an array of cinder cones encompassing an area of.