Newcastle City Council, which took control of the site in 1966, recently completed stage two of the ambitious project and is currently in the process of seeking grant funding to complete the job.

More than 3300 people are known to have been buried in the old cemetery, and more than a third of them were children aged under three, but only 258 graves had been formally mapped so the council commissioned a Sydney-based geophysics company to identify areas where they could dig without the risk of turning up human bones.

GBG Australia used a sophisticated ground penetrating radar in 2012 to identify the location of graves or bones buried beneath the surface. 

The radar doesn’t produce images of human remains, but identifies areas where the earth has been disturbed and determines its chemical make-up.

The electromagnetic frequencies were able to map ‘‘probable’’ and ‘‘possible’’ grave sites and their depth.

GBG’s senior geophysicist Jamie Speer said results showed the shallowest unmarked grave was just 50centimetres below the surface. At 70cm down, many more graves were identified, and by the time the signals had reached 2.5metres underground, large masses of  ‘‘disturbed ground’’ was located.

Sarah Cameron, the senior heritage strategist who has led the council’s project team, said the mapping allowed the council to determine where it could place new paths and trails, and how far down excavations for footings could be dug.

‘‘Fortunately none of the work carried out so far has turned up human bones,’’ Ms Cameron said. ‘‘We found plenty of animal bones though. It’s a fairly forensic exercise – if we find so much as a toe bone we have to notify the coroner, the police, the department of heritage.’’

The site has already been cleared of most of the weeds and overgrown shrubs that have dominated the site for the past few decades. 

From most points Newcastle Harbour and Stockton Bight can now be viewed.

Some of the larger trees had to be removed, and several more will be in the future, but most have been left, including several which have driven roots through some of the historic graves.

A new path connecting King Street and the cathedral is now open, with each step bearing the names of those known to have been buried in the old cemetery.

The oldest known grave is that of Mary Martin who was buried there in 1826, but a number of historians recount burials in the vicinity of the cathedral as early as 1804.

In 2010, Newcastle Family History Society published the most comprehensive register of baptisms, marriages and burials at the cathedral. 

It recorded the names of 3352 people buried in the cemetery, including 1282 children under the age of three, but it is possible  more were buried there because many a poor family was known to have snuck into the cemetery at night to bury a child who had succumbed to typhoid.

The council is keen to begin work on the third and final stage of the project which includes an infant memorial to commemorate the vast number of young children buried there.

Also in the plan is a new sandstone sculpture which will be placed over the mass grave of 30 people killed in the sinking of the Cawarra paddle steamer off Newcastle in 1866.

A rotunda, park seating and viewing platforms will also be built, and the headstones set aside during the  project will be returned to their original placements.

But the final stage is still contingent on the council acquiring grant funding from the state and federal governments. 

Applications are in for heritage funds, but the council is also hopeful  it might attract  grants to encourage tourists interested in history. 

If  successful, the council could begin work on the final stage in July.