Introduction
The Nullarbor Plain is one of earth's great road journeys — a crossing of the vast, flat limestone plateau that extends across the bottom of Australia from South Australia into Western Australia, traversed by the Eyre Highway in one of the world's most extraordinary drives. The name Nullarbor comes from the Latin meaning "no trees," and the southern edge of the plain, where it meets the Southern Ocean in a series of spectacular limestone cliffs, is one of the most dramatic coastal landscapes on the planet.
For most Australians, the Nullarbor is primarily known as the long drive between Adelaide and Perth — a journey of about 2,700 kilometres that takes a minimum of three days and is associated in the popular imagination with monotonous emptiness, expensive roadhouse fuel, and the longest stretch of perfectly straight road in Australia (at 146 kilometres, the longest straight road in the country). This reputation is both accurate and profoundly misleading — the Nullarbor is indeed flat and the drive between roadhouses can be repetitive, but the coastal scenery, the whale watching, and the extraordinary dark sky experiences available along the way make the crossing one of Australia's most rewarding road journeys for those who approach it with curiosity and unhurried attention.
This guide covers the Nullarbor crossing from South Australia's perspective — the major attractions and stopping points, the best wildlife experiences, the geological significance of the landscape, and the practical information needed to plan a crossing that is safe, comfortable, and genuinely rewarding.
The Bunda Cliffs
The Bunda Cliffs extend for about 200 kilometres along the southern edge of the Nullarbor, where the limestone plateau drops abruptly 60 to 100 metres to the Southern Ocean below. These are among the longest unbroken sea cliffs in the world — a continuous limestone escarpment that falls sheer from the flat plain above to the wild ocean below without any beach or rocky foreshore to cushion the transition.
The cliff-edge views accessible from the Eyre Highway are genuinely spectacular — the flat white limestone plain meeting the brilliant blue of the Southern Ocean in a vertical drop of extraordinary drama, with the ocean swell visible far below and the curve of the cliffs extending to both horizons. Several designated viewing areas along the highway give safe access to the cliff edge, and the combination of the geological scale and the maritime wildness below creates a landscape experience that is genuinely unique in Australia.
The cliffs are the best whale watching location on the Nullarbor, as southern right whales and their calves frequently rest in the sheltered water at the base of the cliffs during the winter calving season from June through October. Watching from the clifftop as whales move along the base of the cliffs, surfacing to breathe in the calm water in the cliff's lee, is one of those wildlife encounters that the Nullarbor provides without any advance planning or infrastructure requirement — simply pull off the highway at the cliff viewing areas and look down.
Whale Watching at the Head of Bight
The Head of Bight, where the Great Australian Bight reaches its deepest penetration into the continent, is one of the world's premier southern right whale watching locations. Each year from May through October, southern right whales gather in the warm, sheltered shallow water of the Bight to give birth and nurse their calves in conditions that provide protection from predators and rough seas. At peak season, over a hundred whales can be present simultaneously in this exceptional nursery habitat.
The Head of Bight Interpretive Centre and viewing platform, operated by the Yalata Anangu community, gives the best access to the whale watching experience. The boardwalk system takes visitors to clifftop viewing platforms above the whale nursery areas, giving close-range views of whale behaviour that include spyhopping, breaching, tail-slapping, and the intimate interactions between cows and their calves. The whales are typically visible from September through October at the peak of the season, with July and August also producing excellent viewing.
The Anangu management of the Head of Bight gives the whale watching experience a cultural dimension that standard wildlife tourism lacks. The cultural interpretation available through the visitor centre and optional guided tours connects the whale watching experience to the Yalata Anangu people's long relationship with this extraordinary section of coastline, adding depth and meaning to what is already a remarkable natural encounter.
The Nullarbor's Geological Significance
The Nullarbor Plain is one of the world's finest examples of a karst landscape — a terrain formed in soluble limestone rock where the water drainage system operates primarily underground through a network of caves, sink holes, and underground rivers rather than in visible surface drainage. The Nullarbor's karst system is enormous — the underlying cave network is one of the most extensive in Australia — and several cave systems accessible from the Eyre Highway give visitors direct experience of this underground geological world.
Cocklebiddy Cave, accessible via a short walk from the highway, contains the longest known underwater cave passage in Australia — a submarine tunnel that has been explored to over 6 kilometres by cave divers. The accessible entrance of the cave is dramatic — a large chamber that descends to a subterranean lake of extraordinary clarity — and gives a powerful sense of the scale and character of the underground world beneath the flat plain surface.
Murrawijinie Cave near the South Australia-Western Australia border has a good level of accessibility, with a pathway descending into a large cavern that reveals the cave's character without requiring any specialist equipment or experience. The cave's size and the quality of the speleothem (cave formations) visible from the pathway give visitors an excellent introduction to the Nullarbor's underground geological heritage.
The Famous Straight and the Treeless Plain
The longest straight section of the Eyre Highway — 146.6 kilometres of perfectly straight road through the heart of the Nullarbor — is one of Australia's most photographed road features and one of its most talked-about driving experiences. The optical illusion created by the perfectly flat terrain and the ruler-straight road vanishing to a point on the horizon has a hypnotic quality that demands careful attention to driver alertness.
The "treeless plain" reputation of the Nullarbor is accurate for the central coastal section of the plateau — the area around and south of the highway is dominated by low saltbush and bluebush shrubs rather than trees, creating a silver-grey landscape that extends to the horizon in every direction. This landscape has its own quiet beauty — the light plays on the silver foliage in ways that change through the day, and the emptiness has a quality of profound peace that drivers who stop and get out of their vehicles rarely fail to appreciate.
The slightly elevated sections of the highway away from the true coastal plateau pass through mulga scrub and mallee vegetation that breaks the treelessness of the coastal section and provides habitat for wildlife. The wedge-tailed eagle is the highway's most constant companion throughout the crossing — these magnificent birds feed on the road-killed kangaroos and wombats that accumulate along the highway verge, and dozens of eagles may be seen in a single day's driving.
Practical Crossing Information
Planning the Nullarbor crossing requires attention to fuel management — distances between roadhouses with fuel availability can exceed 200 kilometres, and fuel prices at roadhouses are significantly higher than city prices. Carrying a jerry can with additional fuel is practical insurance against finding an unexpectedly closed roadhouse, particularly if travelling between seasons when some smaller roadhouses reduce their hours.
Water for the crossing should be carried in sufficient quantity for driver and passengers to sustain themselves if a vehicle breakdown leaves them waiting for assistance. The rule of at least four litres per person per day, plus reserve, is the appropriate standard for outback travel in warm conditions. The summer crossing of the Nullarbor — in temperatures that can exceed 45 degrees — requires particular attention to water and to the timing of driving, with the hottest hours best spent in the shade of a roadhouse.
Mobile phone coverage along the Eyre Highway is very limited, with some sections completely out of range. Carrying a satellite communication device — a PLB or a two-way satellite messenger — and registering your crossing with the relevant authorities in advance gives security in the event of a serious breakdown or medical emergency in the most remote sections of the road. The Australian outback's golden rule applies: tell someone where you are going and when to expect you.
The Nullarbor Experience
The Nullarbor crossing has an emotional and psychological dimension beyond its physical and geographical characteristics. The isolation, the scale, the quality of the silence available at any roadhouse stop or cliff viewpoint, and the sense of being genuinely remote from the structures of modern life create a mental space that is increasingly rare and increasingly valued. Drivers who make the crossing without rushing — who stop at the cliff viewpoints, who park at a rest area and walk a short distance into the plain, who watch the sun set over the limestone scrub before retiring to the roadhouse — consistently report a quality of experience that those who rush through in minimum time do not access.
The stars above the Nullarbor are among the finest available anywhere in South Australia or indeed Australia — the combination of genuine remoteness, dry air, and complete absence of light pollution produces astronomical conditions of exceptional quality. Stopping well away from the roadhouse lights on a clear moonless night and spending 30 minutes under the Nullarbor sky is an experience that no photograph or description can fully convey.
The social dimension of the Nullarbor crossing should not be overlooked. The roadhouses along the highway are meeting points for a remarkably diverse cross-section of Australian travellers — grey nomads in their caravans, backpackers in beaten-up cars, interstate truck drivers on their circuit, and everything in between — and the conversations that develop at roadhouse stops have a frankness and warmth that the anonymity of more populated areas rarely produces.
Conclusion
The Nullarbor crossing is not just a road — it is an experience of Australia's continental scale, its geological antiquity, and the extraordinary natural environment that the continent's harsh interior has preserved through sheer inaccessibility. The Bunda Cliffs, the whale watching, the cave systems, the dark sky, and the profound quality of the emptiness all contribute to a journey that is simultaneously one of Australia's most physically demanding road trips and one of its most genuinely rewarding.
South Australia's section of the Nullarbor — from the South Australian border at Ceduna to the Western Australian border at Eucla — contains the most spectacular features of the crossing: the longest stretch of the Bunda Cliffs, the Head of Bight whale watching area, and the highest density of cave systems accessible from the highway. Planning to spend at least three days in the South Australian Nullarbor rather than racing through gives access to all of these extraordinary features.
Approach the Nullarbor with patience, with curiosity, and with the willingness to stop and experience the country rather than simply transit through it. The plain will reward that approach with experiences that the driver who keeps their eyes on the road and their foot on the accelerator will never discover.