Hangman's Cave near the Great North Road. Painting by Ulf Kaiser.
Folklore tells how convicts stood trial here before a magistrate. If found guilty, the convict was hanged and then dropped through the hole in the roof of the cave.

From 1826 to 1834 the Great North Road, built by Sir Thomas Mitchell, was cut through thick bush by convict labour to provide an overland route between Sydney and the Hunter Valley. The labour force was unwilling and unskilled and convicts of the No. 9 road gang rebelled against the overseer. The revolt was put down by military reinforcements and the ringleaders were hung on site and dropped into graves beneath their feet.

Nearly 170 years later the Roads and Traffic Authority (RTA) began work on the realignment of the Old Northern Road at Glenorie. When planners discovered a notation on an old survey plan indicating that convict graves might be in the area, the latest technology was employed to solve the mystery. A team of six professionals under the supervision of RTA surveyors used ground-penetrating radar to precisely locate the unmarked graves so the historic sites could be protected. Ground-penetrating radar is a non-destructive method by which soil layers can be plotted and analysed to show disturbances.

The RTA's heritage work on the Great North Road was greatly assisted by the Convict Trail Project. Initiated by the Bucketty and Wollombi communities, this group brings together a range of organisations and community groups with an interest in the conservation and promotion of the convict-built Great North Road.

The discovery of the convict graves is one of many projects which show how heritage issues can impact on the work of the RTA. The RTA's initiative in heritage work was acknowledged last month in a special commendation given at the 1999 Energy Australia National Trust Heritage Awards.

In presenting the commendation, the judges said: "The RTA is to be commended for their broad range of participation and for the initiatives and scope of their heritage work as demonstrated by these entries. The entries demonstrate the use of new technology and innovation, and an awareness of social responsibility for heritage items which fall within the scope of their work and an acceptance of broader responsibilities, not just of their core business."

As well as the discovery of convict graves, the award recognised the RTA's valuable work in mapping various archaeological sites of the Great North Road; the interpretation by aerial photography of the site of the Mount Victoria stockade, built in the 1830s to house convicts and troops involved in the reconstruction of the Main Western Road to Bathurst; and the RTA Heritage Guidelines.

The Heritage Guidelines are an important strategy for the RTA. Senior Environmental Planning and Heritage Officer, Maria Whipp, sees them as one of the most significant initiatives for heritage at this State government agency in recent years.

"The RTA took great care to develop this document which will help employees take a planned and sensitive approach to heritage issues," said Ms Whipp.

The guidelines were produced in consultation with the RTA Heritage Committee and with the input of archaeologist and heritage specialist, Tracy Ireland. They are distributed to a broad range of RTA personnel, ranging from those involved in on-the-ground siteworks and emergency work to those working on planning and designing the road network in NSW.

"Essentially it is a living document for anyone in the RTA dealing with heritage issues on a daily basis" said Ms Whipp.

The guidelines slot heritage assessment into the RTA's planning process at an early stage. By considering heritage issues when roadwork is being planned, the RTA is hoping to reduce the number of situations where a relic is discovered during construction. However, the guidelines also provide advice on what to do if an unexpected find is unearthed.

"A broad cross section of staff are thinking about heritage now," said Ms Whipp.
"Generally, the RTA Heritage Guidelines are working to raise the awareness of RTA staff of not only RTA-owned heritage items, but other heritage items we might affect in our operation. Being a planning body that deals with a linear service like a road, we cut across many areas. Thus the RTA has a complex task when it comes to environmental assessment and heritage assessment in particular."