Inky sludge oozes to the surface of this beach thanks to a rare natural tar seep.

Happy harbor seals frolic and snooze on this warm, sandy stretch of coast.

At 130 years old and 126 feet tall, it is the largest known example of the rare Torrey pine tree.

Hidden in the Santa Ynez Mountains off Highway 154, this tiny restaurant once served as a stagecoach stop.

A Mysterious Masonic tomb in San Luis Obispo.

An alley covered with 20 years of bubble gum.

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

A collection of massive stacked rocks in Texas includes a snarky note on the benefits of modern technology.

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

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.

An antique narrow gauge railway line still running through the Colorado and New Mexico mountains.

Home of the International Space Hall of Fame.

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

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

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

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

Legends surround this jagged rock formation in the New Mexico desert.

Hidden inside this Arizona fast food franchise is an in-depth exhibit on the famed WWII counterintelligence program.

The graffiti-covered ruins of an abandoned trading post in the middle of Navajo Nation.

This immigrant bridge once spanned the Thames but is now a fixture of an Arizona city.

In Tucson a giant metal snake helps pedestrians cross a busy highway.

Walk through the actual strap iron cells and solitary chambers of Arizona Territory’s first prison.

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