This church is named for one of the most dramatic tales in the early Christian church.

After 400 years of being closed to the public, this monastery's underground tunnels and secret garden are now a museum.

A centuries-old forgotten underworld lies beneath Malta.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

The modern birthplace of Irish freedom.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.

Dublin's "Dead Zoo" serves as a window to Victorian museum design.

The enchanting archway is the only surviving portal into Dublin’s lost medieval wall.

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

This elegant arc of a waterfall marks a religious turning point.

Walk in the footsteps of the gods and straddle two tectonic plates.

An encyclopedic collection of mammal penises.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

The unique waterfall in Iceland's south features a backdrop of geometric black lava columns.

This building has survived for more than a century and remains virtually untouched.

On Gellért Hill, this statue depicts the tragic tale of lovers divided by the Danube.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

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

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

Denmark’s ultra-modern library hides a treasury of rare, unique books.

One of Scandinavia's largest mosaics pays tribute to Danish art and science luminaries.

Bored potato-guarding Nazis etched their thoughts onto a brick storage building in Copenhagen's Meatpacking District.

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

Climb to the top of its spiral spire for spectacular views of Copenhagen.