The site of a defunct mill, that once supplied marble for the construction of the Lincoln Memorial.

An unexpected alley with light shows and nature views.

Once owned by the largest employer in Colorado, these ovens have been abandoned for over a century.

This Rocky Mountain mansion was the luxurious home of the authoritarian leader of a company town.

A little-known hot spring haven right below the highway.

The scene of one of the darkest moments in American labor history has been left essentially untouched since the tragedy.

The ruins of this abandoned fort now stand as a picturesque reminder of America's march West.

This sundial indicates the time based on where you stand within it.

Once a year, the ruins of an ancient village come alive with hundreds of glowing farolitos.

The 7,000-year-old calcium carbonate formation creates a magnificent natural bridge.

A monument dedicated to a local softball team full of clowns.

Once a dining hall for boarding school students, this lodge was a popular haunt for nuclear physicists working on the Manhattan Project.

This museum started as a collection of Manhattan Projects and continues to add exhibits as they are declassified.

This building is a recreation of the gatehouse that separated Los Alamos from the outside world during the era of the Manhattan Project.

Victorian "Fancy Craft" Hair Wreaths and Relics.

A pair of gargoyles peer into unsuspecting passengers at Denver’s conspiracy-packed airport.

This 16-foot-diameter wooden coin has been standing in Iowa City since 2006.

In the middle of a busy airport, a statue honoring the astronaut who told Houston that Apollo 13 had a problem.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

This colossal couch is an unlikely monument to Europe's first female Doctor of Law.

A 200-year-old tavern challenges guests to finish a glass of wine while hanging from a ceiling beam.

For 14 years, this former stray dog greeted every train passenger that arrived in Fort Collins.

After being lost for nearly a century, this historic bell finally returned home after its mysterious theft.

Built in 1981 in collaboration with Andy Warhol, this giant piece of pop art stands on the campus of Colorado State University.