When ecosystems collide in the arid Southwest.

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.

The largest self-built castle in the U.S., six decades in the making.

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

This unusually circular centenarian barn became a Route 66 icon.

The fifth tallest statue in the United States is a shirtless monument to the oil worker.

The surprising home of the iconic Santa Monica Pier Ferris Wheel.

Sitting in the arguable birthplace of the Wild West, this museum holds the largest collection of bronco busting bric-a-brac in the world.

The collection is housed in an exquisite mansion that makes you feel like you've been transported to an Italian villa.

Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

The future of roadside attractions is this sci-fi soda mecca that is home to a 66-foot tall neon pop bottle.

An acoustic anomaly with a mysterious cause.

Historic funicular railway, believed to be the shortest railroad in the world.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

This iconic L.A. bookshop is housed in an abandoned bank—both symbolic and chic.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

This bird-loving brewery is situated in an old municipal bathhouse, nestled beside a 300-year-old windmill.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Artistic tombs, monuments, and a beautiful "Hall of Fame" lurk inside this cemetery.