Rhinog Fawr is an exceptionally rough summit in Snowdonia, in the region of Gwynedd, North Wales. It is 720 m (2360 feet) high and forms part of the Rhinogydd range, being the 3rd highest summit. The terrain is featured by hard sedimentary rock covered with heather, making progress on foot difficult. Llyn Du nestles in crags at the height of 510 m (1673 feet). An easily ascent is frequently taken from the north-east or north-west, through the Roman Steps pass.