The remains of 40,000 humans, meticulously stacked in a tiny churchyard shed.

This Nazi-built amphitheater was constructed on a sacred mountain site used by various German cults.

The prototype for all Nazi concentration camps.

The body of at least one victim of a construction accident was left behind in the collapsed pylon, buried under tons of concrete.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

German-style coffee and cake, just like Oma used to make it.

This Rococo church is known as the most beautiful village church in the world, and does not disappoint.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

The narrowest street in Paris.

Carvings in Turkey's Marble Road may have directed ancient Romans to a hidden brothel.

A charming beach town in Turkey captures all the colors of the rainbow.

This Turkish cave boasts some rather bizarre associations with the King of Mount Olympus.

The oldest cemetery in Belgium.

This fort dates back to 1588 and was colonized by the Portuguese, Dutch, and English and sits prominently on the Indian Ocean where azure water lap the coast.

This peaceful sanctuary is one of the oldest Buddhist temples in Colombo.

Known as the most scenic route in Sri Lanka, this train line is steeped in history and offers an unparalleled view of the country.

This museum housed in a former brothel explores the past and present of sex work in Amsterdam.

A tribute to smugglers and the Butter Wars.

A reconstructed World War I-era communications array that was once hidden in plain sight.

The birthplace of the titular coat and related products celebrates its claim to fame with a statue of a coat.

No shoes allowed on this trail, which is designed to be experienced barefoot.

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