Sir Richard Peninsula is a narrow peninsula consisting of sand which extends from Goolwa, South Australia to the Murray Mouth. It separates the Goolwa Channel which is part of the estuary of the River Murray from Encounter Bay. It is approximately 10 kilometres long and ranges from 500m to one kilometre in width. The peninsula together with the Younghusband Peninsula on the eastern side of the Murray Mouth, is the primary sand dune line defining this stretch of the Australian coastline.