The walls and streets of the ancient city are peppered with penises.

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

Spain's stunning solar energy plant.

This otherwise ordinary close on the Royal Mile constituted the end of the world for Edinburgh’s poorest residents.

A quiet, semi-secret square with statues of Mahatma Gandhi, Virginia Woolf, and a conscientious objectors stone.

A 2000-year-old Roman amphitheater lies just below Guildhall Yard.

This marine reptile was discovered by one of the 19th century's greatest fossil hunters.

Legends say that this Art Deco apartment building almost became Hitler's British headquarters.

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

This centerpiece of the Hollywood & Highland shopping center is a recreation of a long-lost movie set.

The blinking light atop the iconic landmark has been sending secret messages for decades.

Erotic art covers the walls of the largest ancient pleasure palace.

Ancient snack bar of the Roman Empire re-opened.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

In a city that boasts four separate inclined cable railways, this is one of the busiest funicular lines in the world.

This network of narrow, medieval passages has the most delightful name.

A hunk of prehistoric lava rests amid the Gothic architecture of a campus quad.

19th century museum with an eclectic mix of curiosities, from Egyptian artifacts to items on archery history to the skull of the world's oldest horse.

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

A century-old tradition has culminated in a small but singular collection of feline effigies.

After starting as a whimsical tourist attraction that eventually found its way to ruin, these renovated canals offer a lush and exotic locale on the Pacific Coast.

One of the shortest streets in York has an especially odd name.

A hidden three-foot-wide house separates these two regal churches.

Bronze sculpture celebrating the relationship between Churchill and Roosevelt.