Gwy, Nancy 16,500 6,500
RHAYADER (Rhaiadr-Gwy), a market town of Radnorshire, Wales, situated amid wild and beautiful scenery on the left bank of the Wye, about '1 m.
Plinlimmon is notable as the source of five streams - three small: the Rheidol, the Llyfnant and the Clywedog; and two larger and famous: the Wye (Gwy) and the Severn (Hafren).
From the Steddfagurig inn, is Blaen Gwy (the point of the Wye), the course of the streamlet being traceable up to Pont-rhyd-galed (the hard ford bridge), some 4 m.
Wy, or gwy, an obsolete Celtic word for water, preserved in the names of many Welsh rivers - Elwy, Gwili, Wye or Gwy.