The Blue Lake in Mount Gambier, South Australia is a large monomictic lake located in an extinct volcanic maar associated with the Mount Gambier maar complex. It is one of four crater lakes on Mount Gambier
Umpherston Sinkhole, Mt Gambier, South Australia - also known as the Sunken Garden. We ended up here by mistake once, when our rental car died on us on our way to Adelaide.Turned out to be a highlight of our trip.
45 minute Aquifer Tour "which takes visitors in a glass panelled lift down the original dolomite well shaft, from which water was originally extracted. Walk through a tunnel to see the Blue Lake at close proximity.