The only structure left with direct ties to the Salem witchcraft trials of 1692.

This modest post office sits on the site of H.H. Holmes' famous murder castle.

One of only two remaining Victorian-era greenhouses in New York.

Holding the most bodies of any cemetery in the United States.

The end of the 4 Line is also the end of the line for 300,000 souls in one of NYC's most illustrious cemeteries.

This empty Victorian manse on Staten Island is said to be haunted but is actually a real life crime scene.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

The final resting place of the great escape artist, where some still gather to wait for his escape from death.

Hidden in an ordinary Midtown building is a one-room museum dedicated to the greatest escape artist.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

Elevated freight railway turned wildly successful urban park.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

A formerly abandoned mental institute, now back in business.

The name of this famed hospital was once a byword for the horrors of medical and psychiatric care.

One of the largest-ever mental hospitals now sits abandoned, surrounded by 25,000 unmarked graves.

A magical, macabre wax museum, beloved by locals, uses real artifacts to depict an assassination from the French Revolution.

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

Skeletons, medical artifacts, and other obscure and precious treasures all displayed in a wooden pharmacist's cabinet.

One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

A haunting collection of the vanished and disappearing natural world.