Little Blue Lake

Little Blue Lake is a small, circular sinkhole lake located about 5 km south of Mount Gambier in the District Council of Grant, South Australia. Formed as a collapsed doline in limestone karst, it is filled with clear, cold groundwater that appears vivid blue. Notable for its steep limestone walls, depth of around 47 metres, and popularity as a local swimming hole within the Limestone Coast and Kanawinka Geopark region.

Visitors can expect a compact, near-circular sinkhole lake surrounded by steep limestone cliffs and native vegetation. A sealed car park and viewing area sit above the lake, with steep stairs leading down to a floating pontoon at water level. The water is exceptionally clear and cold. There are no shops or lifeguards; the site is set in a quiet rural area off Bay Road/Mount Salt Road, suitable for swimming, snorkelling, photography and picnicking.

A natural collapsed doline formed in the Gambier limestone karst plain, part of the Kanawinka Volcanic Province. The sinkhole formed through dissolution and collapse of limestone and subsequently filled with groundwater, creating a deep freshwater lake that has long been used as a local swimming hole.

Well-known recreational swimming site for the Mount Gambier and District Council of Grant community and a key visitor stop on the Limestone Coast, promoted as part of the Kanawinka Geopark and regional sinkhole trail.