The river Yonne flows northwards and is one of the main tributeries of the River Seine. The source of the Yonne is near Chateau Chinon, in the Morvan regionon the "Mont Préneley" 738 metres above sea level. Once a busy river and floating logs to supply the wood industries.
The river has a slack water lock system and allows access to the Canal du Nivernais, the Canal du Bourgogne and the river Seine.