360° views of the city plus five floors of optical illusions and hands-on science.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

This once-grand marvel of engineering is now 41 miles of scenic hiking trail.

This abandoned cemetery is crumbling into ruin, exposing the artifacts and bodies buried there.

The abandoned husk of a mental institution that failed to save a Jazz Age icon still sits nearly unchanged.

This abandoned factory on the Hudson River once churned out a million bricks a week.

A museum dedicated to "science, history and the arts" little changed since 1915.

Decades after testing the polio vaccine on unwitting patients, this historic mental hospital sits in ruin.

Oldest existing church in New York and the inspiration for Washington Irving's "The Legend of Sleepy Hollow."

This tiny church near Sleepy Hollow contains Henri Matisse's last work, a rose window, and nine windows by Marc Chagall.