Càrn Mairg is the high point on an east-west ridge which connects to the adjoining Munro of Meall Garbh which lies 3.5 km to the west. This broad ridge continues easterly for almost 10 km descending into Glen Lyon at the village of Keltneyburn and also contains two subsidiary tops of Càrn Mairg which are both listed as Tops in the Munro Tables. These are Meall a' Bhàrr (1004 metres) which lies just over a kilometre to the west with a summit which stands on a rocky outcrop. Meall Liath (Grey Hill) has a height of 1012 metres and lies just under a kilometre to the east across a col with an approximate height of 955 metres, there are grouse butts just north of Meall Liath's summit.