This 16th-century monastery has been turned into a surrealist architecture compound.

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

Venice's "Island of the Mad."

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

Stalactites and stalagmites in a beautifully lit cave.

A submerged archeological park still holds the wonders of a Roman Sodom.

Pompeii's less famous neighbor is still revealing her secrets.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

An English artist has turned an unassuming ex-council house into a time-lost house of mystery.

England's oldest surviving hedge maze has been confusing visitors for over 300 years.

The longest hedge maze in the world.

The sign at the garden gate reads: "These Plants Can Kill."

An unusual manor of stunning beauty, born out of a crippling disease.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.

A complex, nine-layer maze on the grounds of a Venetian doge's playground.

Wonderland replication in progress by one persistent man.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Jesus' footprints and the first catacombs in the world.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

A memorial to a dog that inspired rioting in the streets of London.