Coastal Cliffs
The continent and Islands of Australia have some incredible sea cliffs. The most dramatic cliff lines tend to be limestone escarpments, sandstone or volcanic plugs.
Longest cliff Lines
The longest cliff lines in Australia belong to the Bunda Cliffs of the Great Australian Bight. They extend for 160 kilometres from Eucla to the Head of the Bight. In the recent past, this cliff line extended much further Geographers now refer to this immense 820 kilometres stretch of cliff-line as the Great Southern Scarp. This relatively recent geological marvel starts at Wylie Scarp near Cape Arid in Western Australia, before making its way to the coast and forming the 160-kilometre-long Baxter Cliffs. The Baxter Cliffs then turn inland to transform into the Hampton Range, one of the most beautiful escarpments in Australia, before meeting the ocean again at Eucla to form the Bunda Cliffs. This would of a made this line of coastal cliffs a truly formidable barrier dwarfing anything present on Earth today.
The barrier-like Zuytdorp Cliffs in central Western Australia have often been cited as the longest coastal cliffs in Australia. This formidable line of cliffs stretches for 210 kilometres from the mouth of the Murchison River at Kalbarri to Steep Point, the western-most point of Australia’s mainland. However, on careful examination, there are many breaks in this cliff line, especially in the southern regions. The longest stretch of coastal cliffs starts at the Zuytdorp Nature Reserve, near where the wreck of the Dutch ship Zuytdorp lies, then stretches north to Pepper Point just south of Steep Point near Shark Bay
Highest Sea Cliffs
Sea cliffs are much easier to measure and define. Most literature states that it is ‘a sheer rock wall where waves wash onto the cliff’s base’. This can be construed differently by geographers due to tidal influences and the vertical nature of the cliff face. However, my test to determine a sea cliff is if you can throw a rock from the top, whether it would land in the sea. The highest cliff Line in Australia is found on Lord Howe Island. The western face of Mount Gower is an impressive 875 metres of towering massif in the Tasman Sea. Apart from a small scree slope at the cliff base, the sea cliff rises almost vertically for over 800 metres.
On Tasmania’s, Tasman Peninsula, vertical cliff lines comprised of dolerite are a common feature at along the east coast. Cape Hauy has Cape Pillar, the dolerite columns extend down another 275 metres below sea level.
Largest Sea Stacks
Ball’s Pyramid is 562 metres high, 1,100 metres long, and less than 300 metres wide at its widest point at the base. It claims to fame is being the tallest sea-stack on the planet. By definition, a sea stack differs from a sea cliff in that sea stacks are independent rock formations which rise vertically from the sea and not attached to any other island. Balls Pyramid was considered unscalable by Lord Howe islanders, due to the sheer cliffs, lack of landing points, and exposure to the elements.
Highest Sea Arches
The Tasman Sea Arch, located on the Tasman Peninsula east of Hobart, is, without doubt, Australia’s largest, with a height of just over 52. 7 metres above sea level. It’s a grand monument to the erosional power of the sea and dwarfs’ other notable arches on Australia’s coast such as London Arch near Port Campbell in Victoria.
Blow Holes
Going hand in hand with many sea cliffs and sea arches, especially in sedimentary cliffs, are blowholes. These are formed by the continual pounding of wave-action breaking through underlying rocks which create holes in the coastal cliffs,
The Kiama Blowhole is the most famous and probably the most impressive of the many scattered along Australia’s vast coastline. Measuring the height of blowholes if fraught with difficulty. Reports of water rising to sixty metres have been claimed at Kiama although the thirty metres is most probably more realistic. There are some significant blow holes around the Australian coastline and measurements of height are mostly exaggerated, however, most find the sight, sound and spectacle of them alluring.
Sea Cliff Records
GES Record: Longest unbroken cliff line Australia – Bunda Cliffs. Western Australia. 160 kilometres (Source:
GES Record: Largest Sea Arch – Tasman sea Arch. Tasman peninsula. Tasmania 52.7 metres high (Source:
GES Record: Tallest Sea Cliff in Australia – Western slope of Mt Gower. Lord Howe Island. 875 metres high (Source:
GES Record: Tallest sea stack in the world – Balls Pyramid. South of Lord Howe Island. 562 metres high (Source:
State / Territory Records
Highest Sea Cliffs
Australian Antarctic Territory – Unknown
Australian Overseas Territories – (?) Myer Rock. 170 metres
New South Wales – Mount Gower 875 metres
Northern Territory – Rainbow Cliffs. 50 metres (Source: Continent of Extremes. I Read)
Queensland – Pentecost Island 279 metres (Source: 100 Magic Miles. D Colfelt)
South Australia – Cape Torrens. 220 metres (Source: Continent of Extremes. I Read)
Tasmania – Cape Pillar. 275 metres (Source: Continent of Extremes. I Read)
Victoria – (?) Cliffs of Twelve Apostles. 100 metres (Source: Continent of Extremes. I Read)
Western Australia – Womerangee Hill. 250 metres (Source: P Playford)
The Geographic Extremes Society welcomes any input as to the veracity of these records and we encourage everyone to contribute to these extreme records by contacting us to initiate the discussion