One of Ireland's most infamous prisons for rebels including men, women and children.

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

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

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

A hands-off space for graffiti artists to hone and display their skills.

The celebrated eyesore created by starry-eyed sweethearts.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

What once sat in the world’s spotlight is today a largely disused ghost complex.

Pilgrimage site for star-crossed lovers.

Go inside to really appreciate this 500-year-old technological masterpiece.

Countless grotesque faces stare out from this eerie Prague art wall.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

When the rain falls, this drain system turns into a musical instrument.

This Dresden church was purposely rebuilt Protestant after being demolished in World War II.

This unique bridge physically lifts a piece of the road into the air to let boats pass by.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Pre-Nazi swastikas adorn the sculpted pachyderms flanking this brewhouse portal.

The largest bottled beer collection in the world holds over 22,000 unique beer bottles.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.