The Lairig an Laoigh runs roughly parallel to the somewhat grander and far better-known Lairig Ghru which lies some to the west. They both dissect the high granite Cairmgorm plateau which is at about . The Lairig an Laoigh reaches at the watershed between the rivers Dee and Avon and the lairig attains further north in more open country where it skirts Bynack More before reaching the River Nethy. At its highest point the pass is above - the height for a peak to be a Corbett. The Avon and Nethy are tributaries of the River Spey. Between the lairigs Ghru and Laoigh is the central Cairngorn Plateau, with Ben Macdui and Cairn Gorm situated on it, the second and sixth highest mountains in Britain.