Is a perennial river rising north east of Gardiners Gap about 6km north, north east of Cullen Bullen and flowing generally south and east for about 100km into Lake Burragorang. The river is located on numerous topographical maps; the area of interest for this book is on the Cullen Bullen and Lithgow Topo Maps. Headwaters GR 297 132. Coxs River may have also been known by the local Aborigines as Duiwan. Andy Macqueen's research of Surveyor General Mitchell's assistant, surveyor Peter Grant Ogilvie showed that the monthly report by Ogilvie in March 1829 records the native name of Coxs River as, Duiwan. As late as 1896 Gundungurra elder Billy Lynch was reported as saying that the Gundungurra group who had lived in the Megalong - Kanimba area were the "Therabulat", and that was also their name for the Coxs River. Ref: Heritage. Newsletter of the Blue Mountains Association of Cultural Heritage Organisation Inc. July - August 2015. Issue 39; pp.8-13. Named after William Cox, J P, (1764-1837), by Governor Lachlan Macquarie (1762-1824). Macquarie had commissioned Cox to construct a road over the Blue Mountains, which Cox started on 18th July 1814 and completed in March 1815.