Barrenjoey is a locality in the suburb of Palm Beach, at the most northern tip of Pittwater. The headland is made up primarily of sandstones of the Newport Formation, the top third is a cap of Hawkesbury sandstone.[1] Around 10,000 years ago the headland was cut off from the mainland due to the rising sea level; subsequent buildup of a sand spit or tombolo reconnected the island to the mainland (a 'tied island'). It is the location of the Barrenjoey Head Lighthouse, a lighthouse that was first lit in 1881. In 1995 Barrenjoey was gazetted into Ku-ring-gai Chase National Park.[2]
- ^ John Martyn. "Towards a Richer Understanding of Local Geology,STEP INC, retrieved February 22nd, 2018".
- ^ "Ku-ring-gai Chase National Park and Lion Island, Long Island and Spectacle Island Nature Reserves Plan of Management Oct 2014" (PDF). NSW National Parks and Wildlife Service. October 2014. Retrieved 4 September 2018.