Limestone caves with spectacular showcase chambers.

One of the largest open-pit copper mining operations in the entire country.

A reproduction of earth's many biomes.

See massive fossils that are over 200 million years old in northeastern Arizona.

A spiritual vortex among the red rocks in Sedona.

Some of the tallest ancient American ruins continue to inspire awe and curiosity.

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

Strange red rock formations that have been attributed to a higher power for hundreds of years.

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

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

The first declared National Monument in the United States.

Devilish landscape, once cinema home to giant alien bugs, now derelict roadside attraction.

A popular rock that acted as a waymarker for American pioneers.

This prison-turned-museum is a remnant of the Old West's grizzly, violent past.

Native Americans built this circle of stones, which was used to predict astronomical events.

Surrounded by a hundred mile radius of billboards, Little America is a roadside attraction whose primary appeal is hospitality.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A monument to the egos of two railroad magnates that fell into decline along with their careers.

An architect's childhood fantasy treehouse made real.

A beautiful geyser under environmental threat.

One of the smallest towns in the United States.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.