In an alley behind a Fargo bar, you can roleplay as Mario while interacting with a popular street mural.

Hundreds of hidden passageways weave through the old quarters of Lyon.

A colorful piece of contemporary art cheerfully clashes with Lyon's historical architecture.

At night, this memorial illuminates a ghostly outline of a footbridge that connected two sections of the Warsaw Ghetto.

A statue dedicated to the founders of communism.

At less than four inches in height, this iconic fictional character is the smallest public statue in all of Moldova.

Seventy-five miles of limestone caves host more than a million bottles of wine beneath a sleepy Moldovan town.

Once an opulent Art Nouveau hotspot, the Constanța Casino is one of Romania's most beautiful abandoned buildings.

There is a mouldering Jewish cemetery hidden away in the capital of Moldova.

Rubbing the buttons along this statue's coat is considered good luck.

Catch a scenic view of Warsaw's Old Town from the top of a centuries-old dumping ground.

The giant statue and its model solar system honor the native Pole who declared that the Earth revolves around the Sun.

A tree planted by Marie Curie is treasured by the Radium institute that she set up.

In the summer, the area around this sculpture transforms into a vibrant concert venue.

A 20th-century picture show in 3-D.

A hidden art gallery in an abandoned Warsaw fort.

These plaques found across Warsaw commemorate the sites where executions or battles took place during the German occupation.

The last king of Poland was interred in this church nearly 200 years after his death.

A spectacular Petrine Baroque summer palace commissioned for Catherine I by Peter the Great.

This set of concrete chambers resonates according to different notes of octaves.

A series of concentric circles represented a bold new experiment in socialist urban planning, and it notoriously difficult to get around.

A unique sculpture calls the outside of this steakhouse home.

A bronze replica of an elm tree that honors the victims that perished in Pawaik Prison.

The final resting place of more than 200,000 people, this is one of the largest cemeteries in Europe.