As he travelled downstream along the newly discovered River Murray, Charles Sturt found another large river flowing into it. This he supposed from his previous exploration of it in early 1829, further to the north to be the River Darling. He sailed some distance upstream, but stopped when he encountered Aboriginal fishing nets strung across the river. He and his men had a sharp encounter with some Aboriginal people at the junction, but battle was avoided due to the intervention of Aboriginal people he had met with further upstream.

Sturt had left Sydney in November 1829 charged to explore the Murrumbidgee River or failing that the River Darling. He and his men took to the water in a whaleboat on 7 January 1830 near the junction of the Lachlan River. He discovered that the Murrumbidgee flowed into a larger river which he named the Murray, and continuing to go downstream with that, he encountered what he believed to be the River Darling on 23 January. Sturt had tried to maintain good relations with the Aboriginal people along the rivers by making gifts of tomahawks and pieces of metal to them. The people in turn, contrived to 'hand on' the explorer to the next group, thereby negotiating a safe passage for the explorers. This was most noticeable at the junction of the Murray and Darling Rivers where a large and hostile band, armed and ready to attack, confronted the boat party. However a group of men from upstream intervened and averted trouble. Sturt continued on downstream and reached the mouth of the Murray River on 12 February 1830.