The pass runs north-south between the Old Red Sandstone mountain ranges of the MacGillycuddy's Reeks (to the west) and the Purple Mountain Group (to the east). The north-south road through The Gap as the area is also known, goes from Kate Kearney's Cottage in the north, to the highest point at the Head of the Gap at , and down to Lord Brandon's Cottage in the Black Valley in the south. The road from Kate Kearney's Cottage to Lord Brandon's Cottage is in length, with in total elevation change.