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

Underground monastery and fortress.

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

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

Luxury hotel turned into a refugee camp, then turned back into a luxury hotel.

A small but hugely whimsical theater where marionettes play out the "The Battle of Stalingrad."

The fire inside this temple has burned for more than 1,500 years.

This beautiful system of tunnels built into natural rock serves as a centuries old plumbing system.

Iran's colorful terraces are a rare geological masterpiece.

This 17th-century structure is a beautiful testimony to traditional Persian architecture

Mirrors and glass shards cover every inch of this arrestingly beautiful mosque.

This 12,000 year old Iranian cave village has been continuously inhabited for over 3,000 years.

The hottest, driest, and most scenic desert on Earth.

One of the world's largest salt caves is filled with fragile salt sculptures, salt rivers, and huge salt megadomes.

A whimsical bridge uses saxophones to pay tribute to two great men and the European Union.

A magical and peaceful ruined Cistercian abbey in what is now southern Belgium.

This Greek temple, open only an hour a day, was the site of a war of tastes between an architect and an artist.

This modern arts center is built around a gem of late-Baroque architecture.

This massive stone and steel monument remembers a century-old battle that cost thousands of lives and nearly destroyed the city.

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

A magnificent, glittering building tucked into a tiny Bulgarian mountain town.

An abandoned saucer-shaped monument in the Bulgarian mountains.

Sofia's legislative center is continuously reinventing itself.

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