The ruins of this medieval castle in Northern Ireland have inspired artists from C.S. Lewis to Led Zeppelin.

A fantastic castle rumored to be the birthplace of King Arthur.

A curious collection of mechanical moving figures.

A good place to research the Freemasons, esoterica, occultism, and hermeticism.

An enormous cat made of recycled wood scraps.

This structure among the trees was the result of divine inspiration.

The location of the last witch trials of Italy, known as "The Salem of Europe."

This Navarrese cave's history of witchcraft and pagan ritual is not just embraced, but recreated each year.

The first American department store, and home to the largest operating musical instrument in the world.

Huge masonic hall in Philadelphia with lavishly themed rooms.

The taxidermied remains of Charles Dickens' pet raven, which helped inspire one of Edgar Allan Poe's most famous poems.

Dr Barnes' $25 billion private collection of art and arboretum.

A mecca for India's Jains.

Century-old shop, specializing in Occult products.

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

A suspended garden, now gone, once hung in the middle of this abandoned church.

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

An accidentally hidden library containing the ephemeral history of New York.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

An abandoned relic of the city's failed experiment with below ground transit.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

Water and windows define this defensive Italian well.

A monumental underground karstic wonderland is also the water source for over a million citizens of Beirut.