The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

The first plantation museum in the United States to focus on the lives of enslaved people.

This sinkhole was created by a tragic industrial accident and continues to ravage the surrounding landscape.

A 19th-century Gothic, castle-like statehouse by the Mississippi River.

The world-record holder for the longest bridge stretching continuously over water.

For 150 years one family has been producing the iconic hot sauce on a bayou island made of salt.

The LSU mascot lived on the college campus in one of the most impressive tiger habitats in the country.

A swamp and garden tour featuring local wildlife and exotic botanical specimens from around the world.

The lowest point in North America is home to an undrinkable pool surrounded by fields of geometric salt flats.

This crumbling Death Valley mining complex was known for its use of giant, 20-mule team wagons.

Millions of years of oxidation make a drive down this winding Death Valley road surprisingly colorful.

A former utopian healing center created by a huckster and built by derelicts.

Odd outsider art installations surround a Gold Rush-era ghost town.

Dyed by iron oxide over centuries, these sandstone rocks rise thousands of feet into the sky.

A Norwegian-born sculptor created these soaring guardian angels at the entrance to Hoover Dam.

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

A natural formation that resembles a camel resting in the New Mexico desert.

This public square capitalized on a single Eagles reference to bring some life back to an Arizona town.

An homage to everyone's favorite prehistoric cartoon family.

A sharp bend in a dramatic river canyon cut through red rocks.

The final remnant of the Arkansas zinc industry is this historically protected ghost town.

A hillbilly theme park that proved so unpopular the land wouldn't even sell on eBay after it closed.

A pair of giant roadside arrows are all that remains of a former Route 66 trading post.

The highest point in Arizona is an oddly snow-topped peak within the otherwise arid state.