An underground city of ancient quarry tunnels hid thousands of Allied soldiers in WWI.

The compass on its front was a handy tool for 17th-century merchants who needed to know the direction of the wind.

This dilapidated ship carcass covered in trees is a striking sight.

The decorations were inspired by an unlikely missing treasure.

This sidewalk tribute honors Colorado's great culinary creation.

This iconic 1958 tower welcomes air travelers to Tucson with neon-lit letters and architectural style.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

These memorials built by an eccentric bachelor on the side of Interstate 5 cause both wonder and traffic accidents.

The longest and widest floating bridge in the world.

Sports history, made in the Arroyo Seco.

A British pub embodies the spirit of a California legend.

This former stomping grounds of the most eminent astronomers of the early 20th century.

This star-studded Old Hollywood restaurant is where fettuccine Alfredo made its United States debut.

The final resting place of a space program monolith.

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

High on a hill overlooking Los Angeles lives a world famous, high power conical Tesla Coil.

A community gathering place that once housed half-ton tanks and the World's Fair.

This edible park is open to any and all foragers.

A beautiful footbridge with over 2,000 glass sculptures along the walls and ceiling.

The start of the group that straightened the teeth of a nation.

"The Reptile Man's" very own roadside zoo features an albino alligator.

Once a year, thousands of naked cyclists flood the streets of a Seattle neighborhood.

An American city stranded at the tip of a Canadian peninsula where strict adherence to the "49th parallel rule" became problematic.

A statue honoring 44 continuous years of greeting passing ships.