The River Arrow is a river in the Welsh Marches, rising in Powys in Wales, then flowing into English county of Herefordshire.
It rises near Gwaunceste Hill, then flows south-east through Newchuch and Michaelchurch-on-Arrow. It forms a short section of the England/Wales boundary, before flowing into Herefordshire, and through the town of Kington. It proceeds east through Herefordshire, passing Staunton-on-Arrow, Pembridge, Eardisland, Arrow Green, Monkland, Ivington, and has its confluence with the River Lugg south of Leominster, at Stoke Prior.
Its tributaries include the Gilwern Brook.
Another tributary is the Honey Lake Brook which passes through Ivington Green.