Honeydukes Cellar is the cellar of sweetshop Honeydukes, located in Hogsmeade. The cellar is where all of the deliveries are stored for stocking on the shelves of the shop.
A secret passage runs from the cellar to Hogwarts, hidden by the One-Eyed Witch Statue. Few students know about this passage.
The workers come down here and it's bad luck to get caught stealing. Due to the perceived "vermin" problem, several invisible rat traps have been set here.
Take the One-Eyed Witch Statue back to Hogwarts.