Berk's Castle is the main setting of The Trap Door claymation children's show. While this article refers to it as "Berk's Castle", Berk is really only a resident and caretaker. The castle actually belongs to The Thing Upstairs, but he never leaves his bedroom and so Berk has the run of the place. For the most part, all the audience sees of the castle is the cellar, which is where Berk and friends are usually found and is also where the Trap Door is located.
- Cellar - This is where Berk lives along with Boni and Drutt. It's usually a clear room with only the occasional creepy-crawly scuttling about, but can get quite messy if Him Upstairs is overworking Berk with unpleasant jobs or if something emerges from the trap door. On the wall is a small stairway leading to an archway, but Berk never goes through it throughout the entire series. There is a small hole beneath the steps that Boni rests in.
- Kitchen - To the right of the cellar is the kitchen, which is almost never clean. Berk spends much of his time in here cooking for Him Upstairs or just for the fun of it (he is never shown eating throughout the series). A lot of the foodstuffs Berk cooks seem to be alive and still wriggling up until he sends them up the service lift to Him Upstairs' boudoir.
- Bedroom - Not Berk's bedroom, he sleeps in the cellar. This is the boudoir of The Thing Upstairs. The interior is never shown, but Him Upstairs almost never leaves this room. The only times he has entered or left are not shown on-screen and it is unclear how he enters, but he doesn't use the front door or go into any other rooms in the castle. It could be that the never-seen Thing Upstairs can fly and has a balcony next to his room, but that is only speculation.
- Library - Only seen in one episode and it doesn't look much like a library at all, just a miscellaneous room filled with random clutter. All the other rooms in the castle can be described as such too.