One of the last remaining railway viaducts equipped with a transporter ferry.

Constructed by forced laborers, this submarine pen is now a museum and war memorial.

This beautiful example of Victorian engineering is the oldest water-balanced funicular anywhere in the world.

The red letters in the literary pavement leading to the library form a mysterious code.

A island reachable by a causeway at low tide is possibly one of the earliest Western European locations to be identified in text.

These ancient sunken lanes were naturally tunneled into the soft ground by countless footsteps.

Want to properly offend a king? Sculpt a giant hill figure in chalk of him riding out of town.

This former quarry is now a vibrant labyrinth of magical in situ sculptures.

Old Tudor home moved on thick iron rails to a new spot.

At just 25 inches at its narrowest point, it's one of the tightest streets in the world.

These medieval tunnels provided water to the city above through centuries of civil war and plague.

The only remaining U-boat that is still floating never actually saw any action in World War II.

The only microgravity tower in Europe can produce nine seconds of weightlessness.

Mongolian Buddhists believe this monastery in the Gobi desert to be the center of the world's spiritual energy.

The grassy landscape is home to the world's last truly wild horses.

The oldest Buddhist monastery in Mongolia has survived centuries of invasions, political shifts, and religious purges.

This spiritual landmark for practicers of Shamanism is drenched in milk and vodka and covered in blue scarves.

This massive glowering Lenin head gazes out over eastern Siberia.

A decomissioned facility where the German "Transrapid" maglev trains were once tested.

This beautifully designed star-shaped fort was the premier defense system of the late 1500s.

The two massive guns that defended Cartagena Bay.

An off-the-beaten-path monastery in the northern hills of Ulaanbaatar.

Thanks to a spelling mistake this bizarre beaver-tiger hybrid became the symbol of a Siberian town.

Enormous statue of the Emperor of the Mongols.