Geothermal resources are cooled in this oddly-shaped structure before being used for irrigation

Model trains whizz around an extensive room-sized diorama of Kyoto City.

A short tunnel built straight through a magmatic dike.

This secluded village in the Andean wilderness can't be accessed by road.

One of the few surviving gates into Old Goa, the former capital of Portuguese India.

This building is a recreation of the gatehouse that separated Los Alamos from the outside world during the era of the Manhattan Project.

Maze-like streets filled with vibrant murals draw visitors to this Istrian town.

These oddly shaped pink granite formations got their name after being mistaken for massive piles of hay.

A collection of expressive stone sculptures in a scenic and serene riverfront location.

An astonishingly accurate water clock that doubles as an hourly spectacle in this Berlin shopping area.

This 18th-century water provider for Aranjuez was refurbished in 2013 only to be neglected again.

The best-preserved beehive tombs in Oman with spectacular backdrop.

An undeciphered text is inscribed on a mysterious stone slab.

After 400 years of being closed to the public, this monastery's underground tunnels and secret garden are now a museum.

A charming Amazigh village carved into a mountaintop.

This Swedish village shows off its most well-known products in a big way.

This stone tower was built to protect Crete from incoming pirates.

Marvel at this immense work of art that greets arrivals to the city.

A unique Buddhist temple with strange statues, beehives, and dinosaurs.

This kinetic sculpture focuses the sounds of the city when you stand inside.

A grueling 699-step stairway to a heavenly view of the island of Saint Helena.

This enormous gold Buddha statue was hidden inside a stucco decoy for centuries.

One man's journey to return a stone to its point of origin after 200,000 years.

Defy gravity at this fascinating Pyrenees overlook platform.