The Headless Horseman (Sometimes known as The Headless Rider) is an infamous ghost from the folktale The Legend of Sleepy Hollow, which has been adapted into various books and movies. According to legend he's the ghost of a soldier from the Revolutionary War whose head was blown off by a cannonball, and he rides forth at night in search of his head. He's said to be unable to cross running water.
He appeared in The Real Ghostbusters episode The Headless Motorcyclist, but as the title implies rode a motorcycle instead of a horse. The Ghostbusters used holograms to make a bridge over a river look like a street, and when he tried to ride across was stunned long enough for the Ghostbusters to trap him.
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