Bacteria and algae give the salty water its bubblegum hue.

A Roman monument to their own civil engineering prowess.

Romania's "Red Ravine" is a little-known natural wonder that bears a resemblance to the Grand Canyon.

Climbing to the top of the cathedral's bell tower offers sweeping views of these medieval ruins.

No one knows who built this strange cave of worship or exactly why.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

This memorial to the victims of the Romanian Revolution of 1989 is often compared to a potato on a skewer.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

Romania's triumphal arch looks out over Bucharest.

A giant portrait of an ancient king looms over the river.

This tiny river island switches sovereignty every six months as part of a rare, centuries-old agreement.

Abandoned blockhouses from Nazi Germany's Atlantic Wall erode into the sea on a French beach.

The vibrant buildings in the “capital of the comic strip” celebrate the art form that made it famous.

Ivy-covered Medieval tunnels cut through this charming town in France's Loire Valley.

A huge Megalithic chamber tomb located behind a cafe.

Beautiful carved tunnels.

This 1,400-year-old abbey was once a powerhouse for music and intellectualism known across Normandy.

An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

This awesome Spanish castle is so fantastical it was actually used on Game of Thrones.

A landscape decorated with enormous skull sculptures.

When a supermarket opened up shop within a medieval building it became protected by UNESCO on a technicality.

These temples are among the oldest free-standing stone buildings in the world.

The ruins of a megalithic monument sit right in the garden of a luxurious Maltese resort.

This Luxembourg cave is covered in cryptic looking marks left by mining activity.