We know this today, the Yankee Hat paintings are currently the only known Aboriginal art sites in the ACT. The Yankee Hat art sites are located within Namadgi National Park in the Gudgenby Valley in a complex of boulders situated at the foot of Yankee Hat Mountain. Carbon dating of the camp-site deposits in the Yankee Hat rock shelter indicate Aboriginal use of the shelter earlier than 800 years ago. Evidence from nearby sites suggests that people were camping in the area, and presumably painting, as long as 3700 years ago.
The following article from 1931 appears to report the discovery/recording of the Yankee Hat Aboriginal artwork...
The Sydney Morning Herald - 31 October 1931
National Library of Australia
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