The Infinite Libarary

The Infinite Library, also called the Infinite Staircase, Musea or, very rarely, Borgia, is a portal-plane stretching through all other planes of existence and housing libraries or museums. It is an Outer Plane, but it connects mostly to the Shadow Planes. It was created some time in the early period of humanoid development when many similar projects in different planes were conjoined.

The library itself and the articles within it are defended by Immutables.

List of Levels of Musea