The oldest volcanology research center in the world.

Buried next to Pompeii, this lesser-known Roman villa was the opulent vacation home of Emperor Nero's wife.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

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.

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

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

Daily jousts and dancing barrel makers in Munich's mechanical clock.

The prototype for all Nazi concentration camps.

Built to test magnetically levitated elevators, the tower also boasts Germany's highest visitor platform.

The oldest surviving wooden bridge over Rhine lets travelers cross easily from Switzerland to Liechtensten.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

Caves famous for the dragon-slaying saint who lived there.

A historic observatory precariously perched at the "Top of Europe."

The second-highest train station in Europe.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

A museum marks and documents the site of the Titanic's launch.

This Neolithic passage tomb forms part of a World Heritage Site.

The ancient tomb acts as a calendar that keeps perfect time.

This ancient Irish tower could easily have stood in for Rapunzel's prison.

These gigantic skeletons tower over visitors and provide insight into the creatures that once ruled over Ireland.

This permanent collection of preserved bodies taken from Irish bogs is one of the leading authorities on such morbid mummies.

The comedy and tragedy of Oscar Wilde is preserved in a Dublin park, captured in a sculpture of colorful stone.