Long Reef Headland, Sydney, NSW, Australia. Located in the Warringah Council area of New South Wales (NSW), Australia, Long Reef was formed during the Triassic Period over 230 million years ago and is composed of Sydney's oldest geological sediments (from the Narrabeen Group of sedimentary rocks). The chocolate shales, claystones, and ironstones ensure that the headland undergoes constant erosion from the wind and waves. It has also created an extensive rock platform for which the headland is renowned. The headland is exposed to swell from the northeast to southeast and the surf is dominated by a permanent headland rip current. Several strong beach rips can be seen in the photograph.

Long Reef is an important site for many species of migratory shorebirds, which include the ruddy turnstone, bar-tailed godwit, grey-tailed tattler, red-necked stint, black-browed albatross, sooty oystercatcher, Antarctic prion, red-tailed tropicbird, double-banded plover, and the Pacific golden plover. A variety of invertebrates also live on the reef, some of which can be spotted at low tide. They include sea anemones, barnacles, limpets, chitons, gastropods including cowries, blue-ringed octopus, nudibranchs, crabs, sea stars, sea urchins, marine worms, cockles, oysters, sea sponges, tube worms, and cunjevoi. Weedy seadragons can be observed by divers and large areas of Neptune's necklace grow on the reef. (Photograph taken by Adam Weir, Kenthurst, NSW, Australia.)