Filmmaker John Meredith and his son in law, Arnold Greenwood, follow the meandering Wye river from its source on Plynlimon in mid Wales to the Severn estuary near Chepstow, taking in the border-country villages and towns on their way. The only city, Hereford, sits well in this lovely landscape, and we can imagine the walkers’ twinge of regret as life beyond the Aust Ferry crossing beckons.