17th century streets hidden under Edinburgh were once a breeding ground for the black death.

These fantastically named natural pools look like something out of a Scottish myth.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

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

19th century museum with an eclectic mix of curiosities, from Egyptian artifacts to items on archery history to the skull of the world's oldest horse.

The largest oak in England is said to have been the hideout of Robin Hood and his Merry Men.

This magical museum celebrates the life and work of a seminal children's book writer (and occasional spy).

Installed at a chaotic intersection, this gave London traffic cops a place to hang their heavy woolen coats.

An English artist has turned an unassuming ex-council house into a time-lost house of mystery.

Follow the original medieval paths that wind through this intriguing section of the city.

Harry Potter once visited this massive limestone cliff, which was carved by an ancient glacial river.

This Manchester laundromat is hiding something.

This foolish Victorian sea fort was converted to a deluxe hotel.

The forest that inspired Winnie-the-Pooh's Hundred Acre Wood can be found outside London.

It is said the legendary wizard once lived in this sea cave beneath Tintagel Castle.

This haunting stone chasm is a hotbed of mossy rock and English legend.

A house of bones — but nobody is quite sure to whom they belong.

Dating back almost 400 years, the oldest public collection library in the United Kingdom was once the study hall of Karl Marx.

England's most notorious suicide spot.

The names Lúthien and Beren can be found inscribed on the shared grave of the famous writer and his beloved wife and muse.

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

The pioneer of psychoanalysis spent the final year of his life here, still seeing patients on that famous couch.

These ancient sunken lanes were naturally tunneled into the soft ground by countless footsteps.