A moody and picturesque riverside ruin overgrown with vegetation.

The vibrant buildings in the “capital of the comic strip” celebrate the art form that made it famous.

One of the most unusual geological features, recognizable from a dozen hit movies.

A Museum of Psychiatry in a still-operating mental institution.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

A hidden treasure in London with a rich medieval history, and the resting place of many luminaries.

A site where “the ravages of the war are more striking…than any other place in contemporary Spain.”

Astonishing collection of helmets, scientific instruments, and medical models.

An emporium for the weird, creepy, rare, and just plain gross.

World-famous, Pink's still manages to keep its prized cult fetish status.

A centuries-old complex of hand-dug stone chambers has sheltered locals in times of trouble.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

The ruins of an 800-year-old monastery boasts the tallest round tower in Ireland.

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

One part local history, 99 parts gruesome haunted house.

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

An eccentric garden of sculptures crafted in India decorate an Irish green space dedicated to Alan Turing.

A statue in the center of Dublin dedicated to one of their favorite sons of rock & roll.

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

A museum that cashes in on its infamous little people while teaching you a thing or two about the Irish fey.

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

The atmospheric road was never meant to be so creepy.

Northern Ireland's Brobdingnagian stepping stones.

Located in the house where Gustave Flaubert was born, this odd museum has more to do with medical grotesquery than the Western novel.