It was a time when giant crocodiles, marsupial lions and tigers, and mega kangaroos and wombats ruled.
Leading researchers have this week told Chinchilla News fossil sites along the mighty Condamine River are the oldest, richest, and most diverse Pliocene sites in Australia.
While much of the community would be unaware of the significant fossils sites on Chinchilla's doorstep, researchers have been finding fossils there since the 1860s.
Much of the credit for the extensive research belongs to Chinchilla locals Cecil and Doris Wilkinson, who have been carefully collecting thousands of fossils for nearly 30 years.
Mr Wilkinson admitted he had intentionally kept the fossil discoveries quiet for many years, fearful that sites would be pillaged or damaged.
The dedicated duo has donated the majority of their important fossil collection to Queensland Museum, but they do still open their Chinchilla home for visitors to inspect some specimens.
"It's been more than 25 years of work. But while it was work, it was fun as well. "We were the first people to ever see these things."
Queensland Museum and Science Centre's head of geosciences, Dr Andrew Rozefelds, said there was "definitely potential" for tourism off the back of the region's rich history.
"This site contains the most significant Pliocene fauna in Australia," Dr Rozefelds said.
"It is by far the best known, most researched, the most studied site of its age in Australia.
"It's a bit like a big jigsaw puzzle where most of the pieces are long gone."
The principal site is protected by State Government legislation as a reserve and also under the Environment Protection and Biodiversity Act 1999, however many sites also lie on private property.
Access to sites is strictly restricted to accredited researchers.
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