The drawings depict birds, lizards and marsupials, while there are also stencils of human hands and arms and of boomerangs and other tools. There is also a drawing of a wombat, rarely seen in Aboriginal rock art. Australian Museum anthropologist Paul Tacon said the artwork is in 12 layers, the most recent dating to the 1800s. Humans and god-like human-animal composites and realistic and symbolic depictions of birds, lizards and marsupials feature in the paintings. There are life-size, delicately drawn eagles and kangaroos and a rare depiction of a wombat, Dr. Tacon said.

NSW Premier Bob Carr said in a speech to the Parliment he was overawed by the discovery, which he said marked Aboriginal culture at a time when civilisation was blossoming around the world. “This reminds us 4000 years ago, when you had civilisation flourishing in Mesopotamia, when you had the power of Egypt, before China was united, while Stonehenge was being built, we had Aboriginal people in these lands, on the outskirts of the Sydney basin,” he said, adding the exact location of the cave would be kept a closely guarded secret to ensure its protection. “If someone in Italy said they had just found a new Etruscan tomb, that would date back to 700BC. This find is 2000BC. If someone excavating in Athens discovered the ancient foundations of a classical building, this is 1500 years before that.”