The Avon River begins on the south eastern slopes of Mount Wellington, part of the Great Dividing Range. The river to the south, then east, then south by southeast, before reaching its mouth to form Lake Wellington. The Avon has ten tributaries including the Turton River and the Perry River. The Latrobe River also flows into Lake Wellington. This lake empties into Bass Strait through the Mitchell River south of Lakes Entrance. The Avon River drops over its course.