This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

A beautiful Greco-Roman structure houses a well once believed to have healing powers.

This is the largest cemetery in Ireland and the first cemetery museum in the world.

Among the ostentatious rococo ornamentation of this church, an image of death cuts the life-thread.

A former connection to City Island, it has been abandoned since the 1930s.

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

Colin Stokes "got a bit carried away" and built a castle that looks like something out of Tolkien.

St. Mary's Asylum was isolated and abandoned before being converted into a Bed and Breakfast.

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

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

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

This lovely little burbling creek is actually a deadly waterway that has dragged down everyone who ever set foot in it.

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

Shakespeare, David Bowie, Dr. Who, the Saxons, Druids and Romans are all claimed to have all made their mark on these massive man made tunnels.

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

The largest greenhouse in the world is home to over one million types of plants.

Surreal riveted sea forts once protected the Kent shores from German attack.

A unique waterfall that some believe attracts the fairfolk.

The gloomy ruins that inspired Bram Stoker to bring Dracula to life.

Hidden in a grotto 26 feet below Nottingham's oldest hotel, this stylish subterranean drinking den is notoriously hard to find.

400-year-old garden, restored to beauty.

A island reachable by a causeway at low tide is possibly one of the earliest Western European locations to be identified in text.

For centuries no one knew there were hundreds of bones and precious artwork hidden beneath this Swiss church.

The world's largest collection of witchcraft regalia.