Site of a classic 19th-century physics experiment to prove the earth is rotating.

The resting place for anonymous victims of the Danube's dark waters.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

The former private quarters and office of Dr. Sigmund Freud now hosts a museum housing the works of the founding father of psychoanalysis.

An ancient holy well said to be used by the patron saint of sailors and travelers, lost in the boggy west of Valentia Island.

A dilapidated psychiatric facility on the outskirts of Milan where electroconvulsive therapy was developed and Napoleon once lived.

Elaborate tile work in this railway station tells the story of Portugal.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

Ancient catacombs form the foundation for this Rococo orgy of a church.

A massive mausoleum towers over the gravestones in a 19th-century Italian "model village."

This Italian ski resort rose to fame when Benito Mussolini was held prisoner there and then rescued by the SS.

What looks like a link in Gondor's early warning system is actually a centuries-old Italian fortress.

People have been living in the cave houses on this Italian hillside since the Neolithic era.

This zoological museum began as the first great curiosity cabinet.

Eco-village hidden in the foothills of the Alps that created a massive system of psychedelic underground temples.

This half-finished "city of toys" was almost Italy's own Las Vegas.

The astonishing collection of an infamous criminologist.

Natural cathedral designed by Italian artist Giuliano Mauri.

A whimsical bridge adorned with decorative dragons.

This massive subterranean fissure is known as the "underground Grand Canyon."

One of the largest caves in the world open to the public.

During World War II, this rice mill became a Nazi concentration camp.

The venerated body of a 12th century saint is celebrated each year with the 'Race of the Candles.'

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.