The Argo Tunnel is a 4.16-mile (6.69 km) mine drainage and access tunnel with its portal at Idaho Springs, Colorado, USA. It was originally called the Newhouse Tunnel after its primary investor, Salt Lake City mining magnate Samuel Newhouse, and appears by that name in many industry publications from the time period when it was constructed. The tunnel intersected nearly all the major gold mines between Idaho Springs and Central City, and is the longest such drainage tunnel in the Central City-Idaho Springs mining district.
Argo Tunnel in 2009
Argo Tunnel, early 20th century
The Argo Tunnel water treatment plant removes metals and acidity before the tunnel discharge flows into Clear Creek, in foreground.
Algae in the Argo Tunnel's outflow, prior to the installation of a new inner bulkhead and reopening of the portal entrance for tours.
The City of Idaho Springs is the statutory city that is the most populous municipality in Clear Creek County, Colorado, United States. Idaho Springs is a part of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area. As of the 2020 census it had a population of 1,782. Idaho Springs is located in Clear Creek Canyon, in the mountains upstream from Golden, some 30 miles (50 km) west of Denver.
Aerial view of Idaho Springs from the east in 2006.
Bird's eye view of Idaho Springs Colorado, 1882.
Reproduction of ink rendering; shows Idaho Springs, Clear Creek County, Colorado.
Colorado and Southern Railroad locomotive on exhibit in Idaho Springs