The Seventh Level of Moria or Khazad-dûm was a level of chambers, corridors and rooms, being six levels above the Great Gates.[1] The term level or levels in the ancient Dwarven kingdom generally refer to the eastern area of Moria, nearest the eastern gate which was most populated when Khazad-dûm was a mighty city of the Dwarves.
The Chamber of Mazarbul was located on the Seventh Level of Moria.[1]