The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

The prototype for all Nazi concentration camps.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

A dismembered holy head stares out from her beautiful reliquary at the St. Dominic Basilica.

First founded in 1472, this is the oldest bank in the world. Its history may explain why we call financial institutions "banks."

This cheese shop also houses a museum devoted to Dutch dairy.

A fascinating insight into daily life in the Eastern Bloc.

An ethereal glowing blue ocean cave in Croatia.

This black sand beach was crafted from volcanic explosions including the historic Minoan eruption.

An often overlooked ancient site in downtown Athens with substantial history (and nature).

Underneath one of the region's most historic roads lies the home of Plato's successor.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.