An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

When German-Iraqi relations broke down, this embassy was vacated post haste.

A series of modernist treehouse hotel rooms grace the outskirts of an Arctic forest.

Bring your hiking shoes, wool socks, and thermal underwear for a stay in these cozy forest huts.

An Irish church where an 800-year-old mummy is reaching out of his coffin as if to shake hands.

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

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Architectureal fantasy quarter of Rome.

Rome's ancient Etruscan rival, now a park full of ruins.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

One of seven Jewish catacombs in Rome and one of only two open to the public.

A submerged archeological park still holds the wonders of a Roman Sodom.

Museum preserving torture methods from the past.

A curious collection dedicated to human and animal anatomy and pathology.

A beautiful maze marks where three countries meet.

Survival capsules find a second life as a unique hotel.