Knighton is a market town and community on the River Teme, straddling the border between Powys, Wales and Shropshire, England. It lies in …Knighton is a market town and community on the River Teme, straddling the border between Powys, Wales and Shropshire, England. It lies in the traditional county of Radnorshire. Originally an Anglo-Saxon settlement, Knighton is located on Offa's Dyke, the ancient earthwork that divided the two countries. It later became a Norman defensive border town.