A geological oddity topped with a 2,000-year-old pagan temple.

This little medieval church hidden in the center of Yerevan was lost and rediscovered—twice.

Huge stairway leads to this massive gallery.

This medieval manuscript collection has some of the most obscure and ancient texts in the world.

This effigy of Peter the Great is greatly disproportionate.

A marvel of Byzantine engineering under the streets of Istanbul.

1513 Turkish world map, full of European state secrets and snarky commentary.

No one is sure if the world's fourth-largest diamond had been found in a rubbish heap or was pawned by Napoleon's mom.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

The European towns of Brașov and Râșnov each have proud signs reminiscent of the Hollywood sign.

Some of the greatest minds in the history of Hungarian art and science converged in this café.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Macabre astrological automaton clock dating to the late 1400s.

The palace window through which Protestant nobles flung two Catholic regents, thus sparking the Thirty Years' War.

Climb inside an iron crystal magnified 165 billion times its normal size.

A little sculpture with a large wardrobe.

Cozy basement bar sports an inventory of over 2,000 beers.

Brussels' favorite peeing boy has a sister.

The hallucinogenic center of the ancient world.

This legendary city has been a tourist attraction for centuries.

A 2,000-year-old computer demonstrates remarkable engineering and astronomical precision.

An ancient octagonal weather station named for the eight Greek gods of wind.