A once-booming Mississippi River town with a history of racial violence is now eerie and mostly abandoned.

The lowest point in the state of Illinois, at the confluence of the Mississippi and Ohio rivers.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

San Francisco's newly reopened hands-on science museum.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

The unbelievably opulent home built for an infamous newspaperman.

A massive volcanic plug is now a protected area that hosts a number of bird species.

The ghost town that ended up on Ebay.

This dormant volcanic crater has been converted from a roiling pit of magma to a pleasant hiking spot.

This giant temperature attraction created some giant electric bills.

The most magnificent bottle house in a town strangely full of them.

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

An abandoned Jazz Age dream home and con man's hideout in Death Valley.

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

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

An urban laboratory.

The folks at the Devil's Rope Museum want you to get hooked on barbed wire history.

This water tower slanted at an uncomfortable angle off the old Route 66 was an ingenious marketing ploy.

A sculpture made of 10 Cadillacs as a monument to the “Golden Age” of the American automobile.

The Grand Canyon of Texas.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

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

A Prada store in the West Texas desert that is never open for business.

Modern technology and live displays tell the story of the Pacific during WWII for the Internet generation.