Obscurely located within the Penambol Conservation Park, Caroline Sinkhole is an interesting geological feature visible from a purpose-built elevated viewing platform over its edge. Rain water, which seeped into the ground, has been dissolving the limestone bedrock along its lines of weakness for many years. These weaknesses developed into a cave over time as portions of limestone broke away under their own weight. Eventually, the roof of the cave could no longer be supported and its collapse created a cenote. This geological feature is now known as Caroline Sinkhole.
Excavations have revealed evidence that the sheltered overhanging ledge in the sinkhole was once used by the Bunganditj people as a winter campsite. European settlers later also used the sinkhole but as a water source for farming. Today, the sinkhole is a refuge for local wildlife.
It took me twice to find this sinkhole. From Mount Gambier, head south along Glenelg River Road until the turnoff onto Sea Coast Hill Road. Drive past Hell's Hole, which is also worth visiting, then turn right onto Carba Road. And, here's where I first got lost. When you see the conservation park sign, take the track leading into it and you'll soon find yourself in a car park. Then, follow a short walking trail towards the north to Caroline Sinkhole.