The first reference to any feature of the country within a radius of 20 miles of Ulladulla was made by Captain James Cook aboard HMS Endeavour while on his voyage north along the Australian east coast. Two days after his discovery of that coast, at 7am on 21 April 1770, he noted in his private log on 22 April 1770**
270 million years ago mud, silt and sand was eroded from mountains along the east coast of the supercontinent, Gondwana, and deposited here in horizontal layers by ocean currents in a shallow sea. Gondwana had drifted down to the Antarctic Circle so, further south, glaciers carried rock debris from the mountains to the coast. There, icebergs floated north and, as they melted in the shallow waters here, dropped their loads including boulders weighing 10 tonne into the mud and silt.