Monty Python fans will recognize this abandoned mine as the Cave of the Killer Rabbit of Caerbannog.

The cave holds a spectacular array of stalactites and stalagmites, including one shaped like a giant human heart.

Monks in the empyreal Alazani River valley have preserved their 1,000-year-old winemaking tradition.

A beautiful but deteriorating monument of Soviet architecture.

Hidden up a dusty track off the Georgian Military Road is this fascinating waterfall with mountainous views.

This extraordinary, multi-pillared monument depicts the fascinating history of Georgia.

Veryovkina Cave is more than 1.3 miles deep—the deepest known in the world.

Fortified homes of highland warriors that are still in use today.

A cylinder monument with a spectacular vista commemorates a friendship that some say never existed.

The last standing example of an ancient district's teatime tradition.

This neon lit Georgian cave claims to hold the boulder Prometheus was chained to.

The first skyscraper to include a Ferris wheel built into the facade.

Unusual building appears to be haphazardly built from randomly piled bricks.

Small church on top of a huge rock column.

This demon atop the Notre-Dame de Paris looks utterly bored.

Built in 1347, this belfry is one of the oldest in the world and survived intense bombing during World War I.

This fascinating abbey is considered the oldest monastery in the region.

This mysterious sculpture was thought to symbolize a world ravaged by misery.

A treasure trove of fine art is hiding inside this small medieval abbey in Gascony.

The precise origins of this pink sandstone temple are unknown.

The remains of this ornate chapel now act as a portal to a cramped French cemetery.

This 5,000-year-old tomb once had its own hinged door.

This 12th century, partially destroyed, abbey has had several owners and was seized during the French Revolution.

This unusual piece of Renaissance art depicting the bodily horror of crucifixion and skin disease may have been inspired by fungus-induced hallucinations.