Location from Curse of Strahd by Tracy & Laura Hickman, Chris Perkins / Wizards of the Coast
A decrepit windmill on a lonely hill where three night hags grind the bones of children into the flour for their addictive dream pastries.
Old Bonegrinder is a stone windmill perched on a barren hill between the village of Barovia and Vallaki. Its sails turn slowly in wind that shouldn't be there, and the sound they make is less a creak and more a grinding — rhythmic, purposeful, hungry. The windmill once belonged to a legitimate miller. Now it belongs to Morgantha and her daughters, Bella Sunbane and Offalia Wormwiggle — a coven of night hags who have repurposed the building for their trade in dream pastries. The recipe requires ground bone, specifically the bones of children, and the hags acquire their ingredients from desperate Barovian parents who trade their own offspring for a few hours of drugged bliss. The interior smells of flour and something sweet that turns the stomach. The upper floors are where the hags sleep and store their captures. Small cages hold terrified children awaiting the grindstone. Old Bonegrinder is one of the most disturbing locations in Barovia — evil made domestic, horror dressed in the trappings of a bakery.
Also known as: Old Bonegrinder, the windmill, the bone mill, the hag windmill