The Great Ring

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Situated in the Astral Sea, the Great Ring (or the outlands) is a plane that is linked to many other planes. The cities there are associated with different planes, and from time to time cities from the Great Ring actually drift into their respective planes. In the centre of the Great Ring is a huge spire atop which sits Sigil, the City of Doors.

The Great Ring

Atlea and Beyond Stackle