Hawkesbury Sandstone is a type of sandstone prevalent in the Sydney region of New South Wales, Australia. It dates from the Triassic Period.^[1] Well known for its durable quality, it is the reason many Aboriginal rock carvings and drawings in the area still exist. Named after the Hawkesbury River north of Sydney, where this sandstone is particularly common. The Hawkesbury Sandstone is the caprock which controls the erosion and scarp retreat of the Illawarra escarpment.

Other rock types found in Sydney include Narrabeen shale and the younger Wianamatta shale.

part of a 20 metre long petroglyph on Hawkesbury Sandstone, at Ku-ring-gai Chase National Park, Australia

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