This hidden Art Nouveau courtyard is an opulent feast for the eyes.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

This is the oldest Roman-made bridge in the city still existing in its original state.

The "Great Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

This curious, round temple is the oldest still-standing marble building in Rome.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

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

A trough of 700 strange bronze faces runs through a narrow alley in Ljubljana's old town.

Strange rumors surround the artist who created these solemn metal guard dogs.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

This abandoned Slovenian military barracks has become a punky-political art squat.

A whimsical bridge adorned with decorative dragons.

A wedding chapel, vintage clothing shop, and bar all under one roof.

A museum dedicated to the legacy of Bob Moog and his pioneering synthesizers.

This rare basilica nestled right in downtown Asheville is an architectural marvel, inside and out.

This North Carolina museum is keeping the pinball craze alive, with a little Space Invaders on the side.

Mystery surrounds a famous marshal of Napoleon's army.

An abandoned village that doubled as "The Hunger Games"' post-apocalyptic wasteland is up for grabs.

The site of an ancient Mississippian settlement that appears to have flourished during the 10th to 13th centuries.