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.

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

Once connected to the outside world by a single train track, this ghost town is looked after by the National Park Service.

A maritime museum holding the remains of Blackbeard's pirate ship.

A historic coal mine that doubles as a museum and tourist attraction.

A Nesting Doll of Churches.

2300-year-old Roman road connecting the empire.

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

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Jesus' footprints and the first catacombs in the world.

Breathtaking and huge 430 year old maps of Italy.

The world's largest fully steerable radio telescope.

Two insane asylum bodies embalmed by an amateur.

Abandoned railroad tunnel is home to a colony of three million Mexican free-tail bats.

An enormous pink granite batholith, long attributed with spiritual powers by the Tonkawa Indians.