The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

Thanks to a quirk of elevation this gift shop produces magic doughnuts that are found nowhere else on Earth.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

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

A museum dedicated to the alleged Roswell Incident.

Long tunnels run under the ancient chariot racing circuit to the tower.

Giant topiary dog once played a role in a terrorist bomb plot.

Stunning Roman aqueduct used for 1900 years and still standing.

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

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

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

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

Look closely and you’ll notice that the color changes a third of the way up the tower.

The site of the climactic scene from the classic horror film is now a historic landmark.

Home to items never before seen by the public.

The former home of Samuel Clemens and family remembers the happiest period of the author's life.

Why have you never heard of the second most popular tourist site in New York?

The abandoned ruins of America's first private zoo are open for exploration in the Catskills.

The Hudson River School comes alive at this palatial estate.

The original Uncle Sam was actually a New York meatpacker who is buried under this historic grave.

This historic church with a connection to "Uncle Sam" is now a fraternity house.

A man used his Civil War-era fortune to build this sanctuary in memory of his wife.

This relic of 19th-century infrastructure is one of the few remaining coal gas storage tanks in the U.S.