Nirvana

Nirvana is the plane of lawful neutral. It consisted of only one layer where everything was in perfect order: equal parts light and dark, heat and cold, and equal measures of the four elements.
Amaunator's Keep of the Eternal Sun is located in Nirvana along with Mechanus, realm of the Modrons and Inevitables.

Type

Dimensional plane

Location under

The Astral Sea