Howdy Tommi,
Just a question, the area of your rocks isn't by chance around the Glass house MTS?
I just ask because i lived in the Widebay/ Frasier Coast area and those mountains look very familiar to an area i have done alot of research of.
And as a note, Unlike alot of other ancient native peoples, the Aborigines did not make a habit of constructing perminant structures.....they were a nomadic people who travelled to where the food was.
I know of one perminant structure that the indigenous populace did construct and that was coastal fish traps, to aid in feeding the tribes that were on the coast during one of their migration cycles.
I hope that has enlightened anyone, it sure did me when i first was told about it.
Cheers
Grim