There are many granite cliffs, in the form of outcrops and tors, scattered throughout the range, making the Mournes one of Northern Ireland's major rock-climbing areas since the first recorded ascents in the 1930s. The rock forms are generally quite rounded, thus often depending on cams for protection, but with good friction. The 1998 guidebook lists 26 separate crags, with a total of about 900 routes of all grades.