The island is located in the Spirit Realm. Zeniba, Yubaba's twin sister, rules over the island (or at least lives there). Swamp Bottom is the sixth stop the sea Train takes from the track of the Bathhouse. Zeniba lives with her Hopping Lantern in a cottage behind the forest.
The structure of the cottage is simple western style. Zeniba likes to eat western stuff, for example, cakes. In the center of the cottage stands an oven for cooking.