The Huon River is the fourth largest river in Tasmania, Australia. It is 170 km in length, and runs through the fertile Huon Valley. From Scotts Peak Dam at Lake Pedder where it begins, it flows south-east to the Tahune Airwalk, where the Picton River joins, before heading through the rural township of Glen Huon where, just to the south, flows down rapids to merge with the sea water and become tidal. From there it then travels through Huonville, Franklin, and Cygnet (Port Cygnet). When the river meets the Tasman Sea near Surveyors Bay, it is more than 3.1 miles (5.0 km) wide. In the lower reaches, the average depth of wide river is 10 feet (3.0 m) and maximum depth is 39 feet (12 m).