Transfer of the remnant RTA lands created a new opportunity for research and interpretation. HHT historians Joy Hughes, Jane Kelson and curator Fergus Clunie began gathering historic maps of the region. Searching for the location of the original Toll House at Rouse Hill, he unearthed new evidence about the line of the old Hawkesbury Road (1794-1813) on which the pursuit and "battle of Vinegar Hill", an armed conflagration between convicts and troops, took place in 1804. Although the road has long since disappeared, it defined the boundary of the first land grant in the area, the 1000 acre "Copenhagen" given to Captain William Bligh. It also ran close to the surviving kilometre stretch of the old Windsor Road built by convicts in 1812-13 as the first turnpike in the colony between Sydney and the Hawkesbury. The exact location of the battle of Vinegar Hill has long been debated, but the map evidence and line of the old Hawkesbury Road indicate that it most likely took place between Second Ponds Creek and the crest of Rouse Hill, formerly known as Vinegar Hill. A line of very early trees at the edge of the road is believed to date back to the time of the battle.