The Wollondilly River is a river located in New South Wales, Australia. It flows through the Wollondilly Shire and is a tributary of the Nepean River. The river is approximately 100 kilometers long and is known for its scenic landscapes and natural beauty. The Wollondilly River is popular for various recreational activities, including fishing, kayaking, and hiking along its banks. It plays an important role in the local ecosystem and supports diverse wildlife. The river also contributes to the region's water supply and is significant for local agriculture.