Blue-green pools and smooth stones comprise one of Spain’s most idyllic hidden wonders.

Perhaps the most spectacular grotto along the Algarve coastline.

Wonderland replication in progress by one persistent man.

At the foot of a waterfall lies a peaceful swimming lagoon and evidence of over 60,000 years of human habitation.

Historic medieval fortified city in southwest France.

This fascinating abbey is considered the oldest monastery in the region.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

This ancient theater was once the home of fierce gladiatorial battles.

This whimsical castle of grottoes was the labor of love of a French postman, and one of the greatest achievements of outsider architecture.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

A ruined castle made famous in German movies and TV productions.

A Black Forest cuckoo clock theme park features one timepiece big enough to walk inside.

In this brilliant blue spring in Germany, legend has it that a sad mermaid learned to finally laugh.

Wooden pathways run through this rocky landscape, which legend says was created when a dwarven king pulled down his own castle to stop raiding giants.

Between Neo-Pagans and Neo-Nazis, these strange rock formations have a curious cult following and a very strange history.

This proud Teutonic warrior rises out of a German forest heralding a victory and measuring lightning.