The Ouanne () is an long river in central France, a right tributary of the Loing.
Its source is near the small town of Ouanne, about southwest of Auxerre. It flows generally northwest, and joins the Loing in Conflans-sur-Loing, near Amilly.
It crosses the following departments and towns:
- Yonne: Ouanne, Leugny, Moulins-sur-Ouanne, Toucy, Dracy, Villiers-Saint-Benoît, Grandchamp, Saint-Denis-sur-Ouanne, Malicorne, Saint-Martin-sur-Ouanne, Charny, Chêne-Arnoult
- Loiret: Douchy, Triguères, Château-Renard, Gy-les-Nonains, Saint-Germain-des-Prés, Conflans-sur-Loing
References