[3] The Main North Line took over half a century to build, and passengers using the northern portion in Marlborough were primarily catered for with mixed trains, while the southern section was the route of the Culverden Express.
However, after operating for only a month, coal shortages in January 1946 meant that it was cut to thrice weekly, running on Mondays, Wednesdays and Fridays.
As the Railways Department did not operate dining cars at any time during the Picton Express's life, stops were made at Waipara and Kaikoura for passengers to buy refreshments.
In February 1956, just over ten years after the Picton Express began operating, it was replaced by the much faster RM class 88 seater railcars.
When the railcars wore out in the 1970s, they were replaced by a carriage train, which was introduced because of the withdrawal of the rival Lyttelton-Wellington steamer express, operated by the Rangitira in 1976.
In 1988 the Railways Corporation announced it was replacing the Picton Express with a new train along the lines of the successful TranzAlpine between Christchurch and Greymouth launched in 1987.