The Multiverse is made up of an infinite number of planes of existence> Most have never been (and never will be) explored by travellers from Gwelith. A small nuumber of them fall under the dominion of one of the Greater Gods or the Firstborn.
The Inner Planes
The term 'Inner Planes' refers to the four elemental planes and the Ethereal plane that provides access to them. These four planes are the building blocks of Gwelith and the Outer Planes.
The Outer Planes
There are numerous Outer Planes. Some are small, pocket dimensions while others are infinite in size. Amongst these there are many planes that are well known to scholars and fall under the dominion of the Gods.
Judgement is Orloth's realm and home for the spirits of the newly deceased. Here Hammon and Hamaya judge the souls of the newly departed and send them on their way to Heaven or Hell.
The Seven Heavens
The Seven Hells
The Nexus is the home of Ramis the Guardian. At the centre of the plane in The City of Doors, where there are said to be portals to all of the planes of existence.