Local historian Nic Haygarth has delved into their impact both below and above ground.
With daily lives engrossed in screen devices and negotiating life above ground, many people don't give a second thought to what lies beneath.
Janine Mc Kinnon has been caving in Tasmania since the 1980s."It is the place to be because we've got the best caves in the country by a long chalk," she said.
It was "rediscovered" in 1977 on the river by then geomorphology student Kevin Keirnan who went on to become the founding director of the Tasmanian Wilderness Society.
It was originally dubbed Fraser Cave, after then-prime minister Malcolm Fraser, in a tactic to draw attention to the area.
Mr Kiernan returned in 1981 as the campaign against the dam was building.
He and colleagues unearthed evidence of Aboriginal existence dating back to the last ice age; it was evidence of the world's most southerly human occupation. Previously it had been thought the Indigenous population had been coastal but a rich archaeological deposit of animal bone fragments and tools, indicated it had been used as a shelter."This completely rewrote the known Indigenous history of the south west because up until that point there had been no evidence that Aborigines had occupied the south west and here he was standing on countless thousands and thousands of tools," Dr Haygarth said."This was at time when Kevin Kiernan and others were mounting expeditions in the Gordon-Franklin area looking for caves just to show that this was going to be a disaster to flood this area that this was an extraordinary cave system."It was a turning point in the campaign to save the river.