Dave, when was the last train to Maree on SG?
Your inquiry-question made me go back to my book 'Pichi Richi Railway of South Australia' written by Pete Dobre in 2007. It writes that in 1957,the Port Auggusta Line extended to Maree.Maree became the largest railway town between Adelaide and Alice Springs.
On January 18,1878, the first sod of the Port Augusta and Government Gums Railway was turned ,Initially called the Portm Augusta-Quorn Railway,this section of the Great Northern Railway opened in December 1879.
They planned to link Port Augusta with Darwin.Within 2.1/2 years, the line reached Government Gums[now Farina].On May17, 1882, the Port Augusta and Government Gums Railway was officially opened ,South Australia Operated the line.
The line extended to Hergott Springs [now Maree],in 1884.By 1891,the line reached Oodnadatta.During 1927-29,the Commonwealth Railways bridged the gap to Alice Springs.
I hope that this helps in your enquiry.