After moving to Chicago in the late 1880’s, Holmes built what became known as his “Murder Castle” at 63rd and Wallace streets. There, he invited guests, mostly young women, to spend the night; many of the women mysteriously went missing shortly after their stays.
When the cops began investigating, they discovered a number of disturbing sights: a third-floor soundproof room equipped with a gas pipe for asphyxiating his victims and a cellar equipped with an oven designed especially for body cremation.
Holmes’ Murder Castle is now the site of a post office.