Afon Cegin

The river is forded by a minor road near Llandygai, and is crossed by the Cegin Viaduct, which carries the main Chester to Holyhead trainline.

The river passes through the arches of the Penrhyn viaduct, before entering the Cegin pool, an area of tidal saltmarsh.

North of these bridges stone walls leading the river to its entry into Bae Hirael.

The Cegin valley was heavily industrialised in the eighteenth and nineteenth centuries with two railway lines - the Penrhyn Quarry Railway and the Bethesda branch line - carrying slate from quarries in the hills down to Porth Penrhyn to be shipped across the world.

The Lôn Las Ogwen cycle-way and footpath runs beside the river along the trackbed of the quarry railway.