This stamp depicts Locomotive No 1, which is regarded as the first locomotive in New South Wales. Although it was under repair on the day of the official opening (26 September 1855) it had been on a trial run transporting passengers from Sydney station to the Long Cove viaduct on 24 May that year.
The stamp design is based on the restored Locomotive No 1 now housed in the Powerhouse Museum, Sydney.
The locomotive was one of two made by Robert Stephenson and Co. which was shipped from Britain the previous January. The carriages were supplied by Wright and Sons of Birmingham.