The walls of America's oldest masonry fort famously "swallowed" cannonballs.

An 18th-century Spanish watchtower made entirely of seashell and concrete.

A tribute to Ponce de Leon's supposed quest for eternal youth.

A haunted hill that supposedly defied gravity.

Architectureal fantasy quarter of Rome.

This too-low North Carolina railroad trestle is still a notorious big rig executioner.

The world's largest vertical wind tunnel.

The only rotating bar in New Orleans has been slowly spinning since 1949.

The oldest cemetery in New Orleans, resting peacefully for over 200 years now.

In this beloved beach town, a secret seafood haven lies tucked behind a car wash.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

An overlooked memorial honoring the local Washington residents who died in World War I.

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

This imposing Masonic temple a mile from the White House was the first public library in Washington, D.C.

A replica of the steam engine that hauled Queen Victoria's Royal Train is on display at Windsor.

Spain's largest bullring offers a unique glimpse at architecture and history.

A complimentary beverage is offered to the bodega's resident rodents every day.

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

A 16th-century Andalusian palace.

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

Throughout this shopping mall are medieval ruins that were discovered during the mall's construction.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

The first ever diner included on the National Register of Historic Places is famous for its custard French toast.

This nearly 200-year-old restaurant's history includes an exiled French prince, JFK, and a very hungry Daniel Webster.