Renowned mathematician and physicist Carl Friedrich Gauss once worked at this observatory.

The bridge that cost Germany a World Heritage Site.

Along the banks of the River Rhine lies a park that seems unassuming, but beneath the surface lies a long and fascinating history.

The taxidermy remains of the first brown bear to enter Germany in 170 years.

The jaw of one of humankind's earliest ancestors on display at an overlooked geology museum.

This 15th-century Ottoman bridge was modified to keep up with the changing course of the river Erenik.

This bakery and museum offers tours of the tastes and mythology of Aachen's signature spice biscuit—just don't ask for the recipe.

England's "pier at the end of the universe" unites astronomy and contemporary architecture.

Nibble as you learn about Slovenia's longstanding tradition of making beautiful honey cookies.

A maze of crosses marks the jumbled divide between the Netherlands and Belgium.

A trio of hidden hot tubs takes advantage of Iceland's natural geothermal vents.

Staves, storm-calling, and of course, necropants.

These cascading falls resonate throughout the Bulgarian forest.

The Grand Mall in Varna hosts one of the biggest collections of Soviet-era paraphernalia in Bulgaria.

An unfinished complex built for children from around the world sits abandoned on the Black Sea coastline.

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

The ceiling of Prohodna Cave in northern Bulgaria affords a peek at the sky via two deity-sized-eye-shaped holes.

Bizarrely shaped rock formations in northwest Bulgaria come with equally bizarre legends.

A former top secret military tunnel is now stuffed with snow and open year-round to skiers.

The house where Harlequin was born.

The unique design of this former quarry provides ideal acoustics for concerts.

A scale model of the world's largest existing lensed telescope.

Gravity seems to fail at this intriguing Swedish attraction.

The internet as provided by a James Bond villain.