You probably don't live that far from a place ghosts are said to roam. Maybe you don’t think about it until Halloween rolls around, when everyone seems to be ready with a scary story. But some of those ghost sightings may be tied to horrible events from the past—knowing the history of a place sets one up to see and hear things that might otherwise be ignored. And whether or not you believe in ghosts, the stories behind the legends can be seriously disturbing. Read eight spooky ghost tales in a list I wrote for mental_floss.