The Frankland River flows for approximately 400 kilometers through the Great Southern region of Western Australia, making it the longest river on the south coast and the largest by volume in the area. It winds through the Walpole Wilderness area, creating a diverse landscape that transitions from forested upper reaches to the tidal lower sections near its confluence with the Nornalup Inlet and the Southern Ocean. This mix of freshwater and estuarine environments supports a variety of recreational activities, with fishing being a primary draw for anglers seeking both native freshwater species and popular saltwater migrants in its lower reaches.