This Polish cave has housed a dragon, a brothel, and an enduring legend.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

An underground city of salt.

A memorial to the beloved brown bear that served in the Polish army during World War II.

A collection of modern and vintage pinball machines housed in the cellar of a 15th-century building.

Where Stoddart and Connolly suffered in the infamous Bug Pit.

Looking for a unifying history, Uzbekistan finds its answer in a 14th Century Turco-Mongol conqueror... despite the fact he wasn't Uzbek.

Giant cauldrons overflow with Uzbekistan's favorite rice dish at this cavernous dining hall.

An 18-meter-long sarcophagus of a constantly growing dead prophet.

This "tower of death" has acted as an observatory, a religious hub, and an executioner's lair.

Light still pours into the ruins of this ancient Islamic observatory.

Ancient barriers wrap around what was once an important stop along the Silk Road.

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

The celebrated eyesore created by starry-eyed sweethearts.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

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

A fountain standing as a testament to a doomed alliance.

This crucial gathering spot along the "hippie trail" still displays old notes between traveling beatniks and backpackers.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

A marvel of Byzantine engineering under the streets of Istanbul.

This airport also offers travelers the chance to view thousands of years of Turkish history.

This sprawling stronghold has been at the center of some of South India's bloodiest wars.

This colorful colonial neighborhood in Panjim is one of the only Latin Quarters in Asia.