This 15th-century aqueduct with distinctive pointed arches was used for irrigation in the Vinalopó valley.

A well-restored ancient archaeology site gives a real feel for life during the Roman age.

This interactive museum highlights the history and philosophy of one of the world's most difficult sailing races.

Long tunnels run under the ancient chariot racing circuit to the tower.

This chest hospital with a dark, haunted past serves as a fitting set for horror films and a paradise for ghost hunters.

Cursed swimming pool left abandoned is now a favorite of filmmakers and ghost hunters.

The abandoned ruins of a beautiful medieval castle just outside Barcelona.

Experience this Iron Age village the way that its original residents would have.

This abandoned racetrack looks like it is set to hold competitions in the apocalypse.

The Frank Zappa fan club erected this monument to their prog-rock hero to mark a new era of post-Soviet Lithuania.

An abandoned masterpiece of Soviet Brutalist architecture.

This 16th-century cemetery became a recreational park during the Soviet occupation—today it's a little bit of both.

A forest park outside Tallinn full of architectural and artistic curiosities.

An empty relic of the Moscow Olympics crumbles away in Estonia's capital.

A secluded art gallery hidden within the cellars beneath Tallinn’s medieval monastery.

"There's nothing there," and other lies the KGB told us.

Once a bustling fishing port, this semi-ghost town is now more than 90 miles away from the shore.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

Light still pours into the ruins of this ancient Islamic observatory.