UK Upland Waters Monitoring Network (UK UWMN) site. The Afon Hafren lies in the Cambrian Mountains of mid-Wales and from its confluence with the Afon Hore forms the headwaters...
UK Upland Waters Monitoring Network (UK UWMN) site. The Afon Gwy lies to the east of Plynlimon in central Wales and forms part of the headwater system of the River Wye. The...