Another fifty kilometre extension southwest to Dallarnil was approved in December 1909 and opened on 6 May 1913. En route stops were built at Thynne, Marule, Junien, Booyal, Munderbong, Tawah, Stanton and Kukar. However, much of the area was infertile and the prospect of agricultural development was overestimated. Small quantities of sugarcane, railway sleepers, cream, lime and cattle were carried but only in spasmodic fashion.[citation needed]
Two trains a week were enough to meet the low volume of traffic and the service beyond Cordalba ceased on 1 July 1955.[4] The Isis Central Mill purchased the Cordalba-Dallarnil section for intended conversion to 2 feet tramway but road transport was preferred. The rest of the line closed on 1 July 1964 in response to transport of bulk sugar by road and sugarcane by mill owned tramways.