Barrenjoey Head, Broken Bay, NSW, Australia. Barrenjoey Head is a prominent headland located at the northern tip of Sydney (Latitude 33.5° S). The 104 m high headland forms the southern entrance to Broken Bay, a large drowned valley named by Captain James Cook the day after he departed Botany Bay. On 7March 1770, as Cook sailed past the 3.5 kmbay entrance, he sighted the numerous ‘broken’ headlands including Barrenjoey, Lion Island, and the First, Second and Third heads. His journal reports: “…some broken land that appear’d to form a bay … I named Broken Bay.” Along the northern headland, Cook described: “Some pretty high land which projected out in 3 bluff Points, and occasioned my calling it Cape 3 Points.” The southern headland was named Barrenjuee by Governor Phillip, the first governor of the new penal settlement of New SouthWales, when he sailed as part of the first Europeans to enter the bay in 1788. The name refers to the aboriginal name for a small wallaby.
The Nepean-Hawkesbury river system which enters the bay began being settled soon after, with fishermen occupying the coastal areas and farmers (and escaped convicts) spreading up the Hawkesbury and its tributaries in search of fertile floodplains. While much development has taken place along the coastal strip, much of the shoreline and surrounding sandstone plateaus remain undeveloped and part of Bouddi, Brisbane Water and Ku-ring-gai national parks. Barrenjoey is connected to the mainland by a 1.3 km long beach (Palm Beach) andHolocene barrier, the initial 300mwide regressive barrier now capped by stabilized transgressive dunes along its northern third, with a golf course, park and surf lifesaving club along its southern part. An armof the bay called Pittwater lies behind the barrier.
The headland is composed of horizontally bedded Triassic sedimentary rocks. Hawkesbury Sandstone caps the upper third of the headland. It is a massive well-cemented quartz sandstone exhibiting distinctive inclined laminated cross-bedding. The lower two-thirds of headland consist of coarse-grained iron-stained sandstones interbedded with shale and siltstone of the Newport Formation. Both units display strong rectangular jointing which produces large joint blocks which fall from the cliff and collect along the landward margin of the rock platform. It is well exposed to an energetic wave climate with the predominately south swell averaging 1.6 m, and cyclonic wave commonly reaching several meters. The headland is surrounded by a well-developed supratidal rock platform which is widest at its eastern end, while considerable boulder debris covers the platform on its northern and southern side. The entire base is however accessible on foot. While the wave attack expends most of its energy breaking over the edge of the platform and remove debris from the platform, the sheltered cliff itself is retreating more rapidly. This is owing to the impact of subaerial weathering coupled with salt water and spray, which leads to an accelerated decomposition and failure of the cliff face, with gravity and wave constantly removing the smaller debris.
A temporary beacon was established on the headland in 1855, with a light tower constructed in 1865 and the present day sandstone lighthouse and keeper cottages in 1881. The headland, which is accessible on foot, is now part of Ku-ring-gai Chase National Park and offers guided tour of the lighthouse. (Photograph taken 5 March 2024 by JohnHudson, Bawley Point,NSW, Australia.)
Barrenjoey Head, Broken Bay, NSW, Australia. Barrenjoey Head is a prominent headland located at the northern tip of Sydney (Latitude 33.5° S). The 104 m high headland forms the southern entrance to Broken Bay, a large drowned valley named by Captain James Cook the day after he departed Botany Bay. On 7March 1770, as Cook sailed past the 3.5 kmbay entrance, he sighted the numerous ‘broken’ headlands including Barrenjoey, Lion Island, and the First, Second and Third heads. His journal reports: “…some broken land that appear’d to form a bay … I named Broken Bay.” Along the northern headland, Cook described: “Some pretty high land which projected out in 3 bluff Points, and occasioned my calling it Cape 3 Points.” The southern headland was named Barrenjuee by Governor Phillip, the first governor of the new penal settlement of New SouthWales, when he sailed as part of the first Europeans to enter the bay in 1788. The name refers to the aboriginal name for a small wallaby.
The Nepean-Hawkesbury river system which enters the bay began being settled soon after, with fishermen occupying the coastal areas and farmers (and escaped convicts) spreading up the Hawkesbury and its tributaries in search of fertile floodplains. While much development has taken place along the coastal strip, much of the shoreline and surrounding sandstone plateaus remain undeveloped and part of Bouddi, Brisbane Water and Ku-ring-gai national parks. Barrenjoey is connected to the mainland by a 1.3 km long beach (Palm Beach) andHolocene barrier, the initial 300mwide regressive barrier now capped by stabilized transgressive dunes along its northern third, with a golf course, park and surf lifesaving club along its southern part. An armof the bay called Pittwater lies behind the barrier.
The headland is composed of horizontally bedded Triassic sedimentary rocks. Hawkesbury Sandstone caps the upper third of the headland. It is a massive well-cemented quartz sandstone exhibiting distinctive inclined laminated cross-bedding. The lower two-thirds of headland consist of coarse-grained iron-stained sandstones interbedded with shale and siltstone of the Newport Formation. Both units display strong rectangular jointing which produces large joint blocks which fall from the cliff and collect along the landward margin of the rock platform. It is well exposed to an energetic wave climate with the predominately south swell averaging 1.6 m, and cyclonic wave commonly reaching several meters. The headland is surrounded by a well-developed supratidal rock platform which is widest at its eastern end, while considerable boulder debris covers the platform on its northern and southern side. The entire base is however accessible on foot. While the wave attack expends most of its energy breaking over the edge of the platform and remove debris from the platform, the sheltered cliff itself is retreating more rapidly. This is owing to the impact of subaerial weathering coupled with salt water and spray, which leads to an accelerated decomposition and failure of the cliff face, with gravity and wave constantly removing the smaller debris.
A temporary beacon was established on the headland in 1855, with a light tower constructed in 1865 and the present day sandstone lighthouse and keeper cottages in 1881. The headland, which is accessible on foot, is now part of Ku-ring-gai Chase National Park and offers guided tour of the lighthouse. (Photograph taken 5 March 2024 by JohnHudson, Bawley Point,NSW, Australia.)
