High Quality Content by WIKIPEDIA articles! Montes Rook is a ring-shaped mountain range that lies along the western limb of the Moon, crossing over to the far side. It completely encircles the Mare Orientale, and forms part of a massive impact basin feature. This range in turn is encircled by the larger Montes Cordillera, which is separated from the Montes Rook by a rugged, ring-shaped plain.