Woodland river. Beech trees (Fagus sylvatica) on the Banks of the river Lyn in Exmoor, showing autumn colours. In the foreground is a carpet of moss and the steep banks to the left of the river are entirely covered in oak trees (Quercus sp.). The river Lyn lies in Exmoor National Park and flows through a deep gorge past Watersmeet and on to the sea at Lynmouth.