The castle still holds traces of the abandoned Roman fort it was built atop.

Memorials at a Florence railway station remember the citizens who were deported from Italy and sent to extermination camps.

A palatial former bank building now houses what may be the poshest art venue (and former Tesco) in Belfast.

It was once nicknamed "the most bombed hotel in Europe."

Thanks to an acoustic anomaly, this unassuming stone bench has heard one hundred years of secrets.

An accidental trick of light casts the perfect shadow of a pilgrim of the Camino de Santiago against the cathedral wall.

This World War II relic let Allied pilots know they were entering neutral airspace.

An unassuming tribute to engineer William Bald and the workers who built one of Europe's most scenic coastal roads.

A fearsome dragon clings to a corner of Munich's city hall.

A hidden three-foot-wide house separates these two regal churches.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

This Luxembourg cave is covered in cryptic looking marks left by mining activity.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

This 6th-century church has the largest and best-preserved collection of Byzantine mosaics outside Constantinople.

An oddly conical beacon perched atop beautiful Irish cliffs.

Thousands of flowers create enchanting pink tunnels over the city streets.

This early version of the guillotine was used to execute the man responsible for its construction.

Home to the world’s oldest seismograph and a four-ton steel ball that makes its own earthquakes.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

This underground church is topped with a 500-foot cross that is seen by many as a beacon of fascist hubris.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.