An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

A historic London pub with prison cells in the cellar and a "spy room" on the second floor.

A special shop catering to the needs of things that go bump in the night, and also helps kids become writers.

Catacombs turned marketplace.

Rebuilt remains of a temple to Roman god Mithras.

The quaint little store that is said to have inspired a famous Dickens novel was only given its name after the book was released.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

The only university zoological museum in London houses extinct animals, bizarre natural history specimens, and a Micrarium of microscopic creatures.

One part local history, 99 parts gruesome haunted house.

This 1920s Dutch barge is now a floating bookstore.

A tongue-in-cheek arcade where the games are based on everyday life.

Eighty million natural history specimens call this gargantuan museum home.

A monument to a 19th-century Irish woman whose murder inspired several literary works.

The symbolic center of Ireland, this summit also offers panoramic views of the countryside.

This rare and ancient Christian relic is one of Ireland’s oldest freestanding stone crosses.

The remains of a majestic house that was once stood in the crosshairs of the Irish Republican Army.

It's said this geological anomaly was caused when the Devil took a bite out of the Irish mountainside.

A teddy bear sits on a chair watching the sunset from the mountaintop—just as the late Dan Clancy had done since childhood.

Fluffy and friendly alpacas nestled against the border of the beautiful Connemara region.

A massive Celtic cross secretly growing in an Irish forest.

This small Irish village suffered the greatest loss of life when the Titanic sank.

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

This colorful and fiery mural depicts the Irish folk story of the beloved hero Cuchulain.