The Selle (also spelt Celle in the Oise) is a river of Hauts-de-France, France. It is 39.2 km long. Rising at Catheux, just north of Crèvecœur-le-Grand, Oise, it flows past Conty, Saleux, Salouël and Pont-de-Metz before joining the Somme at Amiens. In many places along its course, the river widens to form or fill lakes, much appreciated by anglers and gravel extractors. Several water-powered mills can still be seen including a paper-mill at Prouzel. Brown trout thrive in the clear waters of the river.