The Hundred of Ridley is a cadastral hundred in the County of Russell in South Australia. It was proclaimed on 19 April 1860 and included a portion of the former Hundred of the Murray.
34°44′35″S 139°29′28″E / 34.743°S 139.491°ECoordinates: 34°44′35″S 139°29′28″E / 34.743°S 139.491°E