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

Op-art architecture designed for happiness.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

Major tourist destination known for its bubbling mud-pools and hot thermal springs.

A glacier pocked with ice caves and surrounded by rainforests.

This historic stone bridge has an entire neighborhood clinging to its sides.

Between Neo-Pagans and Neo-Nazis, these strange rock formations have a curious cult following and a very strange history.

Hamburgers are intensely proud of their tunnel beneath the river.

A small but immensely extravagant palace built by the "Night King."

The world's tallest church tower reveals a spectacular view to anyone up to the task of climbing the daunting staircase.

Among the ostentatious rococo ornamentation of this church, an image of death cuts the life-thread.

The prototype for all Nazi concentration camps.

The world's most active stratovolcano is almost always erupting.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

Burial grounds for more than 1,000 bodies deep under the modern town of Rabat.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

Bell tower juts out from a village buried under a lake.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

The bears of Bern have been a city highlight for over 500 years.

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

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

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

A sharp bend in a dramatic river canyon cut through red rocks.