Michael Tolich, operations manager for Mainline Steam Heritage Trust which runs the train, said the passengers mostly visited shops and cafes in town before heading back to Auckland.
A small group of locals welcomed the train from the new bridge on the Porowini Rd bypass.
Mr Tolich said there was a 30-minute delay arriving into Whangarei and a two-hour delay getting back to Auckland because the train has had to slow down at different places.
"The tracks have alarms built into them at various points and when they go off, passenger trains are restricted to 40 kilometres an hour rather than up to 70."
The trip from Auckland took five hours, including a 30-minute stopover in Wellsford, but the return journey lasted seven hours, arriving into Auckland at 12.30am yesterday.
"Everyone enjoyed themselves, judging from their expressions during the journey and when they finally got off. There was a wide range of age groups that travelled."
He said a lot of passengers have emailed him, detailing the wonderful time they have had on the train.
Mr Tolich said should the lines stay open, another trip was planned for the end of the year.
The locomotive hauling the train was built by North British Locomotive Works in Scotland in 1951 and operated on New Zealand railways until 1968.
Mainline Steam completely rebuilt the the locomotive and returned it to service in 2004 and has since travelled all over the North Island on excursions.