While not Turkey's deepest underground city, this subterranean redoubt is the largest.

This abandoned coliseum was intended to be a grand Nazi rallying ground before it was halted at the end of the war.

Roman ruins, natural methane fires and a lovely beach.

Once described as the "Eagle's Nest," this ruined ancient city rests on a remote mountaintop.

A mysterious ancient cemetery with Roman sarcophagi and Lycian inscriptions.

A deadly ancient portal to the underworld.

The largest Neolithic ruins in the world hide a notably clean prehistoric metropolis.

Swarms of dainty flying insects swarm into the Petaloudes Valley to get busy.

A 20th-century picture show in 3-D.

After the famous composer died in Paris, his sister snuck his heart out of the country to honor his wish that it be buried in their native country.

A monument to Poland's famous alleged UFO abduction case.

A small museum in this border city displays the contraband art that has been stolen back from smugglers.

This uber-quaint Polish village is known for its habit of painting elaborate floral motifs on just about everything.

The relics are stored in a silver reliquary, where they can be seen through glass.

A marker honors the brief peace found by a tormented artist in the fictional land of Kcymaerxthaere.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

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

Real bones which are said to have belonged to a Polish dragon.

Boats must transform into railroad cars to navigate this Polish canal.

One of the largest amphitheaters in Europe is a former Nazi gathering place that still stands today.

An underground city of salt.

Poland's oldest salt mine has nearly everything one needs to live underground forever.

The unsettling remnants of a torn down movie set lies nearby the ruined location of the actual Płaszów Labor Camp.

This man-made mound monument was built out of soil from all across the Polish empire.