Bealach nam Brog lies about 20 miles northwest of Inverness in the parish of Fodderty, overlooking the A835 road that goes west past Loch Glascarnoch to Ullapool. The pass separates the high ridge of Ben Wyvis from the lower summit of Carn Mòr, overlooking Loch Bealach Cùlaidh to the east. Thomas describes it as 2 miles NW of Garbat, at the watershed between the Strathrannock River and Garbat River, and also as being between Ferrin-Donald and Loch Broom. The Garbat and Strathrannock both run into the Blackwater, a tributary of the River Conon that flows east from Loch Glascarnoch.