The Ilisos is a river in Greece, primarily flowing through the region of Attica. It is approximately 20 kilometers long and is known for its historical significance, particularly in ancient times. The river originates near the Mount Hymettus and eventually joins the Kifisos River. In ancient Athens, the Ilisos was celebrated for its clear waters and lush surroundings. It was often associated with the poet Pindar and featured in various myths and legends. Today, the river is less prominent but remains a symbol of the natural beauty that once flourished in the area.