A Nazi concentration camp and Anne Frank's place of death.

The site of a concentration camp where inmates were made to take part in one of the largest counterfeiting operations in history is now hauntingly empty.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

Giant eggs, walls of bread, and nightmare surreality mark the largest collection of works by Salvador Dalí.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

This real life asylum of horrors is now an abandoned ruin that hides the unbreakable code to one patient's insanity.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

This historic stone bridge has an entire neighborhood clinging to its sides.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

The world's oldest hologram gallery and the labyrinthine laser laboratory of a holography pioneer.

One of the oldest and certainly best preserved Cistercian abbeys still in existence.

These stark white cliffs were spat up by the sea and are slowly being retaken by it.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

The largest arcade museum in the world chronicles the golden age of video games which ended promptly in 1987.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

Shipwrecks, ruins, and turtles are all that remain on this haunting Caribbean ghost island.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

South Korea's love of the silly photograph is on full display at this goofy collection of trompe l'oeil paintings.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

An open-air sewer system that was covered piece-by-piece over 300 years.

Inspired by "The Starry Night" this Dutch bike path turns into a glowing work of art each night.

The quiet field that inspired one of the most famous songs of all time.