Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

This freshwater spring fills with 10,000 gallons of water per minute.

This Wild West attraction is alive with glitching automatons.

A landscape of massive spherical boulders are the main attraction in this Kansas State Park.

Exact replica of the ancient monument, but much, much lighter.

An experimental, automotive replica of Stonehenge.

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

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

The largest source of fossilized insects anywhere.

The final resting place of American icon Buffalo Bill, and a museum that aids in telling his tale.

The highest paved road in North America winds its way up Mount Blue Sky in Colorado to an altitude of 14,130 feet above sea level.

This elegant Colombian fortress was one of the torture headquarters for the Spanish Inquisition.