 To the east of this are the headwaters of the Dyffryn Mymbyr, a tributary of the River Llugwy which it joins at Capel Curig.To the south of Pen-y-gwryd are the headwaters of the Afon Glaslyn which flows southwestwards towards Beddgelert.Many fine crags are easily accessible from the road, and the area is very popular with rock climbers.