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.

Hundreds of thousands of ancient documents offer a unique glimpse into Jewish life in Cairo.

An ancient Phoenician citadel once stood at the site where Queen Dido first landed, according to legend.

An ancient burial ground believed to have been used for ritual sacrifice.

Once the local rulers had gone these enchanting ruins housed common folk in an almost real life fairy tale.

Brussels' favorite peeing boy has a sister.

A little sculpture with a large wardrobe.

An eclectic art form practiced by untrained masters is celebrated at this museum in the heart of Zagreb's old Upper Town.

Where the lovelorn find a home for their sentimental keepsakes.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

It was once nicknamed "the most bombed hotel in Europe."

These barriers stand as stark reminders of Northern Ireland's troubled past.

For part of the year, this innovative greenhouse is painted white to keep the plants from getting scorched.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

A hugely vast Irish landscape of barren rock that stretches for miles.

This single room has survived the centuries with almost no deterioration.

The ruins of a medieval monastery named after a type of tree.

Ireland's most remarkable collection of these curious cone-shaped houses is worth the buzz.

The house where the writer spent his formative years.

This singular Irish dolmen is more Frank Lloyd Wright than upright stonehenge.

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

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

An eerie, existential museum dedicated to the author of "The Metamorphosis."