Ever since I obtained a 1944 aerial photograph of the Lambton region from Newcastle Library, I was intrigued by this loop of track to the south of Newcastle Road.
My guess was that it was used as a training track for horses.
While researching another unrelated matter in Trove today, I found a 25 June 1921 newspaper article on the Jubilee of Lambton that solves the mystery. The article, in reminiscing on times past, reports that
“Many horse racing events were held at the road known as the Jesmond Hill, from the Dark Creek bridge to the present site of the reservoir.”