Mount Gambier is the second most populated city in South Australia, with a population of 26,878 as of the 2021 census. Located on the slopes of a dormant volcano in the south east of the state, it lies approximately 450 kilometres south-east of Adelaide and just 17 kilometres from the Victorian border. The city serves as the most important settlement in the Limestone Coast region and is the seat of government for both the City of Mount Gambier and the District Council of Grant.
The city is notable for its distinctive geology and natural features shaped by volcanic activity and limestone formations. Blue Lake, which changes from deep blue in winter to turquoise in summer, is a prominent landmark. The surrounding area features numerous sinkholes and caves, including Ewens and Piccaninnie Ponds, which reach depths of 100 metres and are popular for snorkeling, and Umpherston Sinkhole, which contains an underground garden. The Naracoorte Caves nearby are significant for their stalagmites, stalactites, bat populations, and fossil deposits.
Mount Gambier functions as a regional hub offering outdoor recreation including water skiing, swimming, diving, and hiking. Nearby attractions include the Wonambi Fossil Centre, featuring prehistoric megafauna specimens, and the Lady Nelson ship replica, a 60-ton vessel built in 1799. The city provides access to the Coonawarra wine region, known for Cabernet Sauvignon and Shiraz production, and marks the starting point of the Southern Ocean Drive. The city is located approximately five hours' drive from both Adelaide and Melbourne, with direct flights available from both cities.