Beinn Mhòr is most frequently and probably most easily ascended from the south, via the end of the public road into Glen Massan. From here, there is a short hike to Glen Massan, followed by about 400 metres of ascent up forestry tracks and paths, from which the climber eventually emerges onto the open hillside. At this point, the climber returning by the same route should note the position, as there are no paths above this point and entering the forest by any other point could mean getting lost in steep and thickly forested terrain. Despite the lack of paths, the upper slopes are gentle and mostly short grass which provide easy ascent to the summit.