 From Antonito a line was built over Cumbres Pass, along the Colorado-New Mexico border, reaching Durango, Colorado in August 1881 and continuing north to the rich mining areas around Silverton in July 1882.A line was also constructed in 1902 as a standard-gauge line, perhaps in anticipation of possible standard gauging of the entire line, south from Durango, Colorado to Farmington, New Mexico.Originally hauling mainly agricultural products and serving as a deterrent to the Santa Fe building up from the south, the line was converted to narrow gauge in 1923, and later delivered pipe and other construction materials to the local oil and natural gas industry into the 1960s.