River Wye given a Latin name "Vaga", an adjective meaning 'wandering'. The Tithe map references a Vagas Field in both Whitchurch and Chepstow. Philologists such as Edward Lye and Joseph Bosworth in the 18th and early 19th centuries suggested an Old English derivation from "wæg", "wave". The source of the Wye is in the Welsh mountains at Plynlimon. It flows through or past several towns and villages including Rhayader, Builth Wells, Hay-on-Wye, Hereford (the only city on the River Wye), Ross-on-Wye, Symonds Yat, Monmouth and Tintern, meeting the Severn estuary just below Chepstow. Its total length is . The lower of the
Wye Valley Walk Hafren, having passed within viewing distance of the source of the River Wye on Plynlimon near Aberystwyth, a total of . The Wye Valley Walk is marked out by circular yellow waymark arrows, finger posts, and signs showing the path's logo, a leaping salmon. Most of the route follows Public Rights of Way. Some parts are permissive paths where owners have agreed for them to be used. Parts of Plynlimon are open countryside in which there is a right to roam established by the Countryside and Rights of Way Act 2000. The route passes through Chepstow, the Wye Valley AONB,