This ancient burial site is believed to be one of the first earthquake-protected structures in the world.

A dreamy mausoleum honors Persia's most famous poet.

A historic trade hub teeming with gorgeous architecture, colorful goods, and vibrant designs.

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

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

One of the largest and oldest caravansaries in Persia.

In this tiny Iranian town playing on the roof isn't just encouraged, it's the only place to go.

These little castles each held thousands of pigeons.

This vast, water-filled underground labyrinth can only be toured by boat.

The ancient necropolis houses the immense rock-cut tombs of four Persian kings.

Modern-day cave dwellers carve elaborate homes out of volcanic debris.

Hydraulic systems in an ancient underground Iranian city.

A sophisticated astronomical tower built by one of the greatest Persian scholars of the Islamic Golden Age.

Putrefaction plateaus in Iran, where the dead were sent for decontamination before going to their final resting place.

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

Georgia's answer to Easter Island immortalizes the nation's great poets, artists, and leaders in stone glory.

At this rare mosque in Tbilisi, Sunni and Shia Muslims pray side by side.

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

The secret room where early Bolsheviks cranked out propaganda fliers on a smuggled printing press.

Sitting right on the border between East and West Jerusalem this modern art museum is in itself a symbol of Israel's hoped-for unity.

"The prettiest love letters in the world" ... or so said Lord Byron.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

A little-known museum of Ancient Roman and Ancient Greek artifacts.

A remnant of Korea's colonial past lies forgotten in a hip neighborhood in Seoul.