The river rises from the limestone uplands of north Oxfordshire, about 1 miles east of Chipping Norton (coord), and flows southeast past Little Tew; through Sandford St. Martin, where it forms part of Sandford Park's gardens; and through the Bartons: Westcott Barton, Middle Barton, where Cockley Brook joins it, and Steeple Barton — before it joins the River Glyme just east of Wootton (coord).