This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

These ruins in Volvi were once at the intersection of the Eastern and Western Worlds.

The secular incarnation of a religious meditation.

A museum dedicated to a secret military hospital hidden beneath a castle in Budapest.

A stairway to heaven, or to nowhere at all.

A museum in the childhood house of a medical pioneer.

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

Once the home of a hermetic monk, this cave now houses a small church.

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

Thousands of rusting train cars have been slowly falling apart on the edge of Greece's second largest city.

Monasteries on rock pillars, once accessible only by frayed ropes.

Montreal's colorful subway station shows its support of the local LGBT+ community.

The skyline of Montreal includes the silhouette of an unexpected fruit-shaped Canadian staple.

A Montreal deli that was so beloved that it was allowed to circumvent their laws of language.

Montreal's giant farmer's market is a foodie's best friend, especially in the winter months.

A century-old network of freight tunnels underneath the city's historic business district.

An eccentric park and pool.

Chicago's North Park Village was once the largest municipal sanatorium in the country.

A European-style bath house in Chicago.

What was once one of the country's largest confectionary plants is now an abandoned ruin, but is still pretty sweet.

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

A spectacular cave and a beguiling lake.

This remarkable cave was discovered after a shepherd watched bees enter and exit through a small fissure.

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.