The Rivière du Sud-Ouest is a river located in the province of Quebec, Canada. It flows through the Montérégie region and is a tributary of the Saint Lawrence River. The river is approximately 50 kilometers long and is known for its scenic landscapes and natural beauty. The river's watershed includes several municipalities, providing recreational opportunities such as fishing, kayaking, and hiking along its banks. The Rivière du Sud-Ouest plays an important role in the local ecosystem, supporting various wildlife species and contributing to the area's biodiversity.