Rock carving created 1,300 years ago 75 feet off the ground.

This once-grandiose behemoth of a monument from the socialist era now sits quiet and closed up.

This historic black and white monastery is one of Bulgaria's architectural jewels.

This massive concrete sculpture is said to be the heaviest communist monument on Earth.

"Holy Wisdom" overlooks the city that became its namesake.

A vast Communist-era exhibition space in the Bulgarian capital.

A collection of art from Bulgaria's time as a communist state.

A striking symbol of the Bulgarian capital.

17th century puritan church with connections to the Salem Witch Trials.

The longest and tallest aqueduct in Britain can actually be sailed across.

Created as a punny statement about genetic engineering this monstrous hybrid statue has become a beloved icon.

A familiar otherworldly creature guards this 12th-century Scottish abbey.

The strange behavior of a tween led to allegations of witchcraft and a curse being placed on anybody within earshot.

The charmingly disheveled clock tower of Tbilisi's puppet theater.

Ancient rock-hewn town that witnessed key events of Georgian history.

A sweet symbol marks the place where torturous executions were once carried out.

360° views of the city plus five floors of optical illusions and hands-on science.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

The old fire station features a mural that has more to it than first meets the eye.

The apartment building where JFK's assassin lived after defecting to the Soviet Union.

This Minsk museum has cat coffee, cat chess, cat art, and even a cat "staff," which visitors are free to take home.

Thanks to its heroic service during WWII this Soviet castle has been turned into a monument towered over by a brutalist titan.

Locals spent years successfully fighting to save this beloved Brutalist behemoth from demolition.

The second-longest pier in the U.K. stretches a whole kilometer into the Irish Sea.