A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

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

A marvel of Byzantine engineering under the streets of Istanbul.

The Swedish flag over this small naval fort signals that the nation is at peace.

Outside a Viking museum sits a modern-day runestone made by a Swedish runemaster using traditional methods.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

A man has revenged his true love's betrayal through tears and stone genitalia.

This "preacher's pulpit" once used for pagan ritual, is home to a new, and dangerous ritual.

An art project designed to encourage people to explore and investigate their surroundings more closely

An opportunity to walk in the footsteps of Nobel Peace Prize winners.

Norway's oldest cathedral still in use.

In a city of wooden houses, this watchtower was vital for early fire detection.

A triumphant marble and bronze fountain depicting a 15th-century Hungarian king and his hunting party.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

Budapest's Communist-era statues, banished to the suburbs.

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

The blood-soaked ruins of the castle where the murderous Blood Countess was walled in alive.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.