An abandoned saucer-shaped monument in the Bulgarian mountains.

Two churches shoot bottle rockets at each others' bell towers in an unusual Easter celebration.

Hidden in a secluded Greek cove is a pristine beach marred only by the rusting smuggler's hulk stranded on its shores.

The hallucinogenic center of the ancient world.

Monasteries on rock pillars, once accessible only by frayed ropes.

This former Nazi labor camp is now a poignant memorial, complete with giant Soviet-style monuments.

A sculpture park of the tossed aside relics of the USSR, from Stalin to a massive Soviet emblem.

A little church on a tiny island looks like something from a fairy tale.

An 18th century wonder of the world, lost in WWII, re-created at the Catherine Palace.

Museum celebrating the achievements of the Soviet space program.

Immortal combat in a Moscow museum.

The gorgeous entrances into the city's underbelly look more like grand halls than subway stops.

It's hard to believe the dizzying patterns covering this abandoned mine are completely natural.

This building holds the embalmed remains of the leader of the Bolshevik Revolution.

Moscow's other, lesser known kremlin is a fairytale-like cultural complex modeled after Old Russia.

Dr. Strangelove-esque tours reveal the inside a bunker once reserved for Stalin himself.

The best-preserved ancient theater in the world.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

The Avenue of Mausolea is a series of grand palatial tombs.

Submerged trees jut ghost-like out of an idyllic turquoise mountain lake.

This Tibetan monastery has survived multiple attacks and is also a sky burial site.

The former stronghold of the Malla Dynasty has remained virtually unchanged since the 17th century.

Named after the Goddess of Harvests, Annapurna is the deadliest member of the Eight-thousanders club.