Outlands

The Outlands are the plane of True Neutral and infinitely large, but they’re also a disc with the Spire in the middle, and the outer edge studded with a succession of towns. Each town is built around a permanent gate portal leading to an outer plane, and each town takes on some of the personality of the town to which its connected. Rarely, if a town’s personality becomes too much like the outer plane to which its connected, it will “fall” into that plane and become part of Carceri or the Beastlands or whatever its connected to, and a new town will gradually be built in the Outlands.