But this week their stories finally came to light through a new Wollongong City Council film.

Patients afflicted with the contagious and deadly disease, also known as consumption, were sent from around NSW to the Waterfall State Sanatorium from 1909 to 1949.

Before the discovery of penicillin, it was believed the cool mountain air and fresh food from orchards and dairies surrounding the hospital, north-west of Helensburgh, could offer a cure.

However, about 4000 people died at the sanatorium over 40 years.

Isolated and desperate for news of their families and former lives, patients would sometimes walk down to the Waterfall rail line in the hope of glimpsing passengers who could toss them newspapers out the train window.

This same isolation has plagued them in death, right up until 2011 when the cemetery was officially rediscovered.

Lost in an apparent bureaucratic bungle when it was handled to Wollongong City Council in 1967, the graveyard is now covered in vines, with most headstones buried forever and those still standing cracked by bushfires or fallen trees.

Map markings showing the cemetery's location were discovered 18 months ago when the council was investigating the rezoning of environmentally sensitive land at Helensburgh, and last year councillors resolved to prepare a conservation plan to decide what should be done with the cemetery in the future.

Now, the council has launched its haunting short film - Not Forgotten: The Story of Waterfall General Cemetery - as well as the community consultation period for the conservation plan.

Speaking in front of a small gathering of family members of those buried at Garrawarra on Thursday night, Lord Mayor Gordon Bradbery told of the pain he and others felt in rediscovering "one of the saddest chapters in our city's history".

"This particular site holds great significance for Wollongong, but its significance extends far beyond our city and is an important part of the history of NSW ... being part of the only state-run facility for the treatment of tuberculosis," he said.

"This was the equivalent of what we might call a lepers' colony; they were isolated and pushed aside from mainstream society for fear of contagion."

But, he said, the city now had the chance to do something about the cemetery's lost history, thanks to "a spark of memory".

One of these sparks came from Kanahooka resident Robert Muggeridge, 73, who appears in the film. He has long treasured papers documenting the death and burial of his father's sister, Gladys Muggeridge, who died at Garrawarra on September 7, 1927.

Her burial cost five pounds and five shillings and she was aged 19.

"I really think that bringing this into the open is a great closure for me, to think that something that could be done for my aunty," Mr Muggeridge said.

For Gold Coast residents Jody Faraone and her mother, Mary Wolfe, along with Mary's sister, Margaret Docker, travelling to Wollongong this week was the final step of a long search to find their long-lost relations.

Mary and Margaret's grandmother, Josephine Minister (nee French) died of tuberculosis at Garrawarra in 1922, aged 24, just three years after her older sister, Gertrude French, was buried there when she was just 22.

Josephine left behind a four-year-old daughter, Mary Eileen French - Mary and Margaret's mother and Jody's grandmother - who died several years ago without even knowing how her mother died.

Ms Faraone has been researching her ancestry for 18 months and, when she discovered the Garrawarra link, began working with the council to help uncover more information about the lost cemetery.

"It's an identity thing for us, it's creating an identity for our whole family because we can now know where we came from, where our ancestors have been and how they died," Jody said.

With the launch of the film, the council is now asking Wollongong residents, and those from around NSW who may have family buried at Garrawarra, to submit their ideas about how it should manage the future care of the rediscovered cemetery.

The public exhibition period is open until November 15.

More information is available at www.haveyoursaywollongong. com.au/projects/waterfall-general-garrawarra-cemetery.