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

Frida Kahlo's childhood home, now a museum of her life and works.

Single runway interrupted by a busy road that cuts across its middle.

Introducing the Green Fairy to her fawning masses.

Less a museum than a bizarre fantasy world created by artists and engineers.

This haunting tombstone comes complete with a heartbreaking story of love and loss.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The encased skull that is widely believed to belong to St. John the Baptist.

The famous winding walk at Chartres is surrounded in mystery and myth.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

This massive library holds what was once the largest book collection in the world.

France's most famous cemetery, with some of its most curious tombs.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Visit the monolithic tomb of America's most famous general.

A little lighthouse in New York City, surrounded by mysterious stories of insanity-driven construction.

Curious crustaceans support an obelisk from ancient Egypt that now stands in modern-day Central Park.

A former insane asylum despised by Nelly Bly and Charles Dickens is now fashionable apartments.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

One of only two commuter aerial tramways in the United States.

A crumbling hospital from the 1850s on Roosevelt Island.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

A drawbridge named for a potentially intersex Polish national who fought alongside George Washington during the American Revolution, and an example of "Pulaski Red".

The factory for the popular Dumbo location, the Greenpoint shop is a quiet gem.