southwesternmost range of the Columbia Mountain system, in southeastern British Columbia, Canada, extending for 200 miles (320 km) north from the Washington (U.S.) boundary between the Interior Plateau (west) and the Selkirk Trench (east), in which flows the Columbia River. Originally known as the Gold Range (a name now restricted to the narrow easternmost ridge), the mountains were renamed Monashee, Gaelic for “mountain of peace,” by an early prospector, David McIntyre. The Canadian Pacific Railway crosses the range south of Mount Monashee (10,650 feet 【3,246 m】), which is the highest peak in the range. Gold, silver, copper, lead, and zinc are mined in the southern foothills.