The Sydney Railway Company (formed in 1848) built a freight terminal at Darling Harbour and opened the access rail line in 1855. Tied to the fate of Darling Harbour, the rail service struggled for custom in the 1860s, but revived in the 1870s to handle farm produce and wool. By 1891, all Sydney’s exports passed through Darling Harbour.
Soon a new line was needed, from Liverpool to Darling Harbour. In the event a route around Rozelle Bay and Pyrmont was approved in 1914 and opened in January 1922. This line was heavily used until freight terminals were built at Port Botany and Chullora. Darling Harbour traffic mainly ended in 1984, although it was used occasionally, such as a weekly wheat train to the Edwin Davey Flour Mill until 1996 when the loop closed.
The rails enjoy a second life as the Metro Light Rail, carrying passengers. The first section, from Central to Wentworth Park opened in 1997. In 2000, it extended to Lilyfield, and it is now expected to use the full extent of the old line, to Dulwich Hill.
Wikipedia, Sydney Metro Light Rail