Perhaps the most spectacular grotto along the Algarve coastline.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.

Three bridges and one giant canyon make up this fantastic Spanish settlement.

A huge musical instrument played by the ocean.

The world's largest wooden structure.

This quirky UFO-shaped curiosity is often mistaken for the airport’s control tower.

The final resting place of a space program monolith.

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

The dramatic upward-curving roof is one of the most iconic examples of Googie architecture that still stands today.

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.

This historic church is named for abolitionist Henry Ward Beecher and the ruse to arm his fellow abolitionists.

Visit the monolithic tomb of America's most famous general.

A giant chess set, minus the psychedelic drug trip.

From the Difference Engine to the Cray-1, all under one roof.

One of the largest Marian shrines on the West Coast stands rather unexpectedly in Silicon Valley.

The most confusing clock in New York.

Hidden in plain sight on the Hudson River is an abandoned train station where nature has taken over.

This evocative New Jersey statue memoralizes the Polish victims of a Soviet massacre.

Thomas Edison's home and final resting place also boasts an impressive garage, where some of the earliest electric cars are on display.

Take a step into the workshop where Edison and his employees revolutionized the world.

This water tower commemorates the invention of the transistor on this site in 1947.

In the power of this waterfall, Alexander Hamilton saw the potential for industry.

This old-fashioned candy shop, ice cream parlor, and diner served as the setting for one of TV's most controversial series finales.

Scary metal statues adorn some of the signature buildings of Burlington, VT.