Colorado

Now a national historic site, this mill operated from 1913 to 1943, processing ore brought via the 22,000 foot Argo Tunnel. At the time it was built, it was the largest mill of its type in the world. It is now a tourist attraction.

A three-story, hand made, medieval-style castle under construction since 1969. The castle is being built entirely by one man, Jim Bishop, who calls his structure "a poor man's Disneyland." It is built primarily of native stone gathered from the surrounding...

A group of several prisons including the "Supermax," a state-of-the art $223 million Federal Prison, which is known as "the Alcatraz of the Rockies." It's perhaps the flashiest of the nine-state and four federal prisons located in Fremont County, Colorado....

Underground command center for monitoring the skies and space for hostile incoming weapons. Cheyenne Mountain was built with the knowledge that it would be a primary target for a nuclear attack, and it is perhaps the most fortified large underground...

This museum houses more than 50,000 rare old photographs, papers and artifacts relating to Colorado railroads. Outside, displayed on 12 acres, is a collection of over 50 narrow and standard gauge locomotives.

America's longest and highest narrow gauge steam railroad, runs between Chama, New Mexico, and Antonito, Colorado, a distance of 64 miles through mountainous terrain, with elevations as high as 10,015 feet, at Cumbres Pass, Colorado. Built in 1880, to serve...

Denver's much maligned $5 billion airport, opened in 1995. It was one of the largest civil works projects in American history. It covers 53 square miles.

Drop City was a community that formed in the hills of southern Colorado in the late 1960s, which become a sort of icon of the rural 1960s communal living that seemed to be blooming at that time. Singled out by the media as exemplary, Drop City was known for...

This disposal cell, near Bodo Canyon, in the hills above the town of Durango, Colorado, was built by the DOE to contain 2.5 million cubic yards of radioactive tailings and buildings from the days of uranium processing at a mill in town. The mill operated (...

The Durango Uranium Mill was one of two uranium recovery plants in Colorado set up secretly in 1943 to produce uranium for the Manhattan Project. Uranium from this site, and the other in Uravan, was shipped to the new secret refinery in Grand Junction, now...

Made by Herbert Bayer in 1955, making it probably the first "earthwork" done within the context of contemporary art, this piece is maintained and visible at the Aspen Institute's Aspen Meadows campus in Aspen, Colorado. Down a nearby path is Anderson Park,...

Located at 11,153 feet in elevation, the Eisenhower Tunnel is the highest vehicular tunnel in the nation's interstate system, and and probably the highest in the world. Built in the 1970's, the 1.7 mile and long tunnel has two bores, one for eastbound and one...

A large mechanized infantry base, with 137,000 acres and around 15,000 military personnel, plus 3,000 civilians. Additional maneuver activities take place on the 245,000 acre Pinon Maneuver Site, 100 miles southeast, acquired in the 1980s. Infantry divisions...

This was the site of a former uranium mill, removed and recently cleaned up as part of the federal Uranium Mill Tailings Remediation Act Project. Also known as the Climax Mill site, it covers approximately 114 acres. The mill operated for 19 years, and shut...

A radioactive waste disposal site for material from a former uranium mill, removed as part of the federal Uranium Mill Tailings Remedial Action Project. The Climax Mill, located on the Colorado River in the middle of Grand Junction, operated from 1950 to 1970...

This Department of Energy uranium mill and laboratory was originally founded as a source for uranium for the Manhattan Project. It later became the center of the government-initiated uranium mining boom of the 1940s and 1950s, propelled by the defense...

A 29-acre disposal cell created by the DOE in 1995 to contain the contaminated tailings and mill buildings from a uranium mill in Gunnison, Colorado, six miles away, which was cleaned up as part of the federal Uranium Mill Tailings Remedial Action Project....

Former uranium mill site, with tailings. Underwent clean-up as part of the federal Uranium Mill Tailings Remediation Act Project. Much of the material was moved to a disposal site six miles east of town.

A complex of museums and exhibits, located next to a rural RV park, features a display of 7,000 tropical invertebrates, giant insects, and artifacts from tropical areas of the world, collected by the museum's founder, who amassed one of the largest collections...

A diamond mine at 8,000 feet in the Rocky Mountains near the Wyoming border. Went into full operation in June 1996, then went bankrupt in 2000. One of only four diamond mines in the country, which together make up less than 1/100th of one percent of the world...

The Leadville mines were a major producer of lead, zinc, silver and gold ores. It is a historic mining district, with many underground mines.

The main site for Lockheed Martin's Astronautics division is a 5,400-acre industrial site, with numerous production, test, and space simulation facilities, and over 70 laboratories. The Astronautics division designs and manufactures space launch vehicles,...

Lowry is a closed Air Force Base in suburban Denver that is being redeveloped into a network of businesses, schools, and new urbanist housing developments. The base was closed by BRAC in 1994, and buildings began being demolished in 1996. Lowry started out in...

There are two disposal cells at the former uranium mining and processing center near the town of Maybell, in the northwestern corner of Colorado. The east cell is the repository for wastes from the uranium mine and mill that operated here from 1955 to 1964,...

The second highest operating observatory in the world, located at 14,100 feet. Operated by the University of Denver, the 2100-square foot observatory complex was completed in 1996 and has twin 28-inch telescopes that can be operated remotely.

A 6.2-mile railway tunnel through the Continental Divide in the Rocky Mountains, completed in 1928. The longest main-line railway tunnel in the USA.

Operated by the Department of Energy, this multiple laboratory facility is engaged in research and development in renewable energy and related technologies. Some of the facilities include: Solar Energy Research Facility (SERF) houses 42 laboratories for research...

A disposal cell for 800,000 cubic yards of radioactive soil and building debris from a uranium mill site 15 miles away in Uravan. The mill operated from the 1930s to 1963. In 1942, the mill became one of two in the USA used to produce uranium for the...

Uranium mill site, cleaned up by the DOE as part of the Uranium Mill Tailings Remediation Act Project. The operations left radioactive mill tailings which have been placed in mounds on site, and at a disposal site is one mile from Uravan, 15 miles northwest,...

A guided tour that goes 1,600 feet into the historic gold mine, which was in use between 1904 and 1971. Authentic equipment is used to demonstrate drilling, dynamiting, and the loading of ore.