To the archaeologists, the site by the Jordan River, on the outskirts of present-day Hobart, Tasmania, did not look particularly promising. But when they began digging, they uncovered an extraordinary treasure trove: millions of artefacts, representing the oldest evidence of human habitation in the southern hemisphere.
For more than 40,000 years, the riverbank was an important meeting-place for Tasmanian Aborigines, who converged on a broad floodplain to trade goods, hold ceremonies, and bury their dead. The spot was still being used as late as 1828, 25 years after Europeans first colonised the island.
The dig was ordered after Aboriginal groups voiced concern about plans to construct a bridge across the Jordan, as part of a new four-lane highway. Archaeologists were astounded by what came to light. "It has the potential to give us a glimpse into an unknown part of world history and the spread of Homo sapiens across the earth," said Rob Paton, who led the dig.
Although Dr Paton's report describes the site as being of "extremely high scientific significance", the Tasmanian government is resisting pressure to re-route the bypass road, claiming that the bridge will not destroy or disturb it. Opponents, however, point to concrete pylons which will be sunk into the grassy floodplain, and plans to create a massive in-fill of rocks.
While the ancient campground is internationally significant, it has particular meaning for Tasmanian Aborigines, whose heritage and history were virtually wiped out during the brutal settlement process.
Much of the Jordan valley was home to Aboriginal people, and three major tribal groups congregated regularly on the floodplain through the millennia. Wild cherries and other bush fruits grew in the area, which – as well as offering plentiful water and fish – was full of kangaroos and wallabies to hunt.
Michael Mansell, legal director of the Tasmanian Aboriginal Centre, says: "That's a place that really strikes at our heart, and is about our identity, our past and our future. When you stand down by that levee, you can feel the presence of our ancestors, of the old people and the children."
Archaeologists say the site could rewrite Aboriginal history in Tasmania and Australia. Digging eight test pits, they found 1,440 artefacts – including tools, stones and spear tips – and concluded that three million objects lie buried. "They're stone artefacts, they're used for day-to-day living, cutting and sharpening," says Dr Paton. "It's that day-to-day stuff that really is rarely found. To get a snapshot of what life was like 40,000 years ago is really quite unique, not just for Australia but for hunter-gatherer sites anywhere in the world."
With approval for the bridge expected to be granted soon, conservationists and Aboriginal groups have appealed to the federal government to intervene. One of the independent MPs propping up Julia Gillard's Labor government, Andrew Wilkie, has called for the site to be National Heritage-listed.
Mr Mansell accuses the Tasmanian government of "cultural vandalism", saying: "We thought they would share our excitement about this discovery, but instead they just saw it as a handicap to their highway. They really have no appreciation of anything that's different from their white culture. To them, white heritage is sacrosanct, but Aboriginal heritage, they're happy to build straight on top of it. You wouldn't see them pouring rubble or building a bridge over the top of Port Arthur [the convict heritage site in Tasmania]."
In Tasmania, Aborigines were rounded up and killed or shipped to offshore islands in the early 19th century. One massacre of men, women and children took place in the Jordan River valley, triggered by the spearing of a white shepherd.
Across the island, little trace remains of ancient indigenous culture. Coastal middens date back only 5,000-6,000 years, and inland caves were occupied about 14,000 years ago. Consequently, the riverbank site – where an estimated 300-400 people are believed to have converged regularly – is a real find.
Aboriginal people are prepared to mount a blockade to prevent the bulldozers going in, according to Mr Mansell. They are also awaiting a Supreme Court ruling on whether the Tasmanian Heritage Council acted correctly when it refused to step in and protect the site.
The state government says the A$177m (£108m) road has been in the planning for more than 20 years, and is essential infrastructure. It has examined eight alternative routes, but says none are viable, and they would add A$80m to A$140m to the cost of the project.