The world’s first penitentiary, meant to be humane, drove men insane.

Once a black market electronics marketplace, now an otaku shopper's paradise.

At first glance, this area seems like just another city park, but the lush landscape hides a dark past.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

Extremely famous in his native country, this Cracovian painter is all but unknown beyond Polish borders.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

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

The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

A statue honors the children who fought Nazis in Poland.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

The prototype for all Nazi concentration camps.

This 14th-century temple is also known as the "Temple of the Golden Pavilion" for its gorgeous gilded reliquary hall.

A beautiful bamboo trail tucked in this famous Japanese shrine.

The 10,000 Torii shrine.

This 700-year-old street food market features baby octopus and soy donuts.

The sound of swaying stalks in this stunning grove has been named a governmentally recognized sound.

Glasgow's memorial to the International Brigade volunteers from Great Britain who fought and died in the Spanish Civil War.

Eight naturally mummified bodies in glass coffins are housed in an underground crypt.

Spanning the El Chorro gorge, this pathway used to be one of the most dangerous crossings in the world.

Spain's unique Mosque-Cathedral has been a place of worship for both Muslims and Christians throughout its history.

A curious carving hides on a marble column in the Mosque-Cathedral of Córdoba.

The powerful party began with a secret meeting in this shikumen in 1921.

A giant scale model giving a sneak peek at what urban planners see for Shanghai by 2020.

The once highest point in China blends symbolic design with a kick of adrenaline.