The Janon is a small river that rises in Mont Pilat in the Massif Central of France near to Saint Étienne. It runs for 13.9 kilometres (8.6 mi) through mostly built-up country to join the Gier at Saint-Chamond. The valley of the Janon and the Gier is a natural line of communication between the coal mines of Saint Étienne and the port of Givors on the Rhone. For many years there were plans to build a canal along this line.