In 1840 Patrick Leslie started with stock from a New England station, then the most northerly settled district in New South Wales, and squatted Toolburra and Canning Downs (at ), the first stations on the Condamine River, before the river had been identified as a tributary of the Darling River. Leslie met explorer Allan Cunningham at the home of Hannibal Hawkins Macarthur in Parramatta. In 1840 Leslie, accompanied by a convict named Peter Murphy, followed in the footsteps of the explorer. On the return trip to Sydney he marked a trail by cutting into the trees. This became known as "Leslie’s marked tree line".