Colorado's only true geyser is hidden within the San Juan National Forest.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

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

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

This spectacular track has run continuously since 1882.

When ecosystems collide in the arid Southwest.

The highest bridge in America was built for an almost unnervingly small amount of money.

The largest self-built castle in the U.S., six decades in the making.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

Inside this shop, visitors are treated to a unique blend of natural history and art.

The haunted reputation of these abandoned Colorado train tunnels is probably not helped by the terrifying spiked fence.

The superstar of Cold War nuclear bunkers has been featured in countless films but is now barely operational.

The clock that sets them all.

Curios, scientific antiques, oddities for sale.

A home covered with elaborate mosaic and other pieces of art.

While comics are the main attraction at this megastore, the second floor plays host to an exhibit fit for a museum.

The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

A downtown park built on top of unclaimed graves.

This modern antique shop is a museum for 1980's Saturday morning cartoon culture.

Texas's oldest bakery serves authentic German pastries, including legendary strudel.

This massive oak tree has ties to the first native tribes of the region and the founders of Texas.

An abandoned mine where dreams of quicksilver trickled away over 75 years ago.