Some 80,000 Delft Blue tiles line the inside of this Amsterdam walkway.

Tables of secondhand books fill the inner courtyard of this 17th-century stock exchange.

Christ's blood allegedly preserved in a Belgian town.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

The compass on its front was a handy tool for 17th-century merchants who needed to know the direction of the wind.

Potato-peeling mannequins, Inca art, and a dangling tuber mobile help trace the history of fries at this Belgian museum.

This triumphal arch celebrating the Sun King's conquest of Lille is a masterpiece of military architecture.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

You can spot this teeny tiny stained-glass window from the Bonifacius bridge.

The world's oldest known salt mine.

An Austrian house of bones filled with hundreds of intricately painted skulls.

The statue of a cursed knight is said to come to life every 100 years.

Piran’s oldest square is laden with history and a beautiful 18th-century reservoir.

A memorial dedicated to the 29,000 Istrian freedom fighters of World War II.

This narrow fjord-like bay is the largest ria in the Mediterranean Sea.

The Renaissance-era courthouse is a relic from the fortified town's centuries of Venetian rule.

One of the best-preserved Roman amphitheaters is still used today, but for less brutal events.

Elaborate tile work in this railway station tells the story of Portugal.

This ex-prison dates back to the Middle Ages.

A collection of old neon signs from all over Poland line a secluded courtyard.

The silly symbol for an underground protest group is now scattered around the city.

An ornate plague column – built to celebrate life – claimed the lives of numerous artisans during its construction.

This renaissance château was home to an infamous witch hunter who sent a hundred suspected witches to their deaths.

A church of bones, decorated with 40,000 human skeletons.