The Odet is a river in western France, which runs from Saint-Goazec into the Atlantic Ocean at Bénodet. The name of the town of Bénodet comes from the river; ben means river mouth in Breton.
The river runs past, or through, the towns of Bénodet, Combrit, Plomelin, Quimper, Ergué-Gabéric, Briec-de-l'Odet, Langolen, Coray, Trégourez, Leuhan and Saint-Goazec. It is 62.7 km long and its basin area is 724 km².
The river is popular with kayakers.
In 2021 an article published in the Bulletin of the French Prehistoric Society reported that archaeologists had interpreted the Saint-Bélec slab, a 4,000-year-old stone rediscovered in 2014, as a three-dimensional representation of the Odet valley. This would make the Saint-Bélec slab the oldest known map of a territory in the world. According to the authors, the map probably wasn’t used for navigation, but rather to show the political power and territorial extent of a local ruler’s domain of the early Bronze age. Measures of the slab were 2.2 metres long and 1.53 metres wide.