The Carlisle River rises in the Otway Ranges in southwest Victoria, south of the settlement of Carlisle River and flows generally north and then west, joined by two minor tributaries, before reaching its confluence with the Gellibrand River, west of the settlement of Carlisle River. From its highest point, the Carlisle River descends 61 metres (200 ft) over its 9-kilometre (5.6 mi) course.[2]