 The River Marden flows in a westerly direction to the south of Quemerford, then turns north and passes under the A4 on its way to Calne.A tributary of the Marden, the River's Brook, passes north of Quemerford.According to etymologists, the name is derived from the Old English Cynemaeres-ford, meaning the ford at the royal (cyne) boundary (maere) or lake (mere).