German explorer Ludwig Leichhardt and his companions headed west from the Darling Downs in 1848. They were never seen again and the disappearance of their expedition remains one of the great unsolved mysteries of Australian exploration.

Friedrich Wilhelm Ludwig Leichhardt was born in Prussia in October 1813 and became fascinated with exploration at an early age. After some study in languages and science, Leichhardt emigrated to Sydney in February 1842 and later that year began making field observations of the Hunter region in New South Wales.
In 1844 he began an unprecedented horseback expedition across Australia, travelling from the Darling Downs to Port Essington, north of Darwin. He was accompanied by nine volunteers, including two Aboriginal guides, who were given the names Charley Fisher and Harry Brown. The party departed on 1 October 1844 from Jimba Station (now known as Jimbour). They arrived on 17 December 1845 at Port Essington, having travelled nearly 4,800 kilometres. They were celebrated as heroes when they returned to Sydney.

A year later, Leichhardt attempted a second major expedition across the breadth of Australia, intending to travel from the Darling Downs to what is now Perth. The expedition team were forced to return after six months due to heavy rain, fever and famine. Undaunted, Leichhardt prepared to reattempt the crossing, setting off on 3 April 1848. Allan Macpherson, owner of Cogoon Station, and several of his workers farewelled the party as they headed towards the sunset. They were the last people reported to have seen the group.
Despite attempts to find the expedition, little evidence of the cause of their mysterious disappearance was ever found. A brass plate and a burned gun were discovered by an Aboriginal stockman around 1900 in the Sturt Creek region. They were wedged into a bottle tree on which the letter ‘L’ had been carved. This suggests that Leichhardt’s party made it as far as Western Australia. Before he left, Leichhardt was awarded the London Royal Geographical Society’s Patron’s Medal in recognition of the ‘increased knowledge of the great continent of Australia’ he had gained by his first expedition. He was celebrated as the nation’s most daring young explorer and honoured posthumously. He was only 35 at the time of his disappearance.
