The company has announced it will run the trip in September, taking up to 94 paying passengers on its Silver Fern railcar over Arthur's Pass to Greymouth, Hokitika and Westport.
The initiative was part of the company's new growth strategy, and came as it rode a wave of ''spectacular growth'' in Chinese passenger numbers, Dunedin Railways chief executive Murray Bond said.
The number of Chinese tourists taking train trips was up 160%, to ''well above'' 2000 passengers, last summer, he said.
''And there's only one direction that will go, and that will be up.''
The growth would be further bolstered by the West Coast trip, which represented the first time Dunedin-based trains had ventured over the Southern Alps since a trip by the Otago Excursion Train Trust in 1982.
All going well, the West Coast trip could become an annual or even twice-a-year fixture, Mr Bond indicated.
''We're confident there's a market out there.''
The announcement comes a month after Dunedin Railways unveiled a timetabled passenger train service to Moeraki and Oamaru, on top of its regular seasider and Taieri Gorge trips.
For a six-day guided West Coast trip package including including meals and accommodation, couples will pay $1749 each, and individuals $2148.
Passengers will depart Dunedin on September 7, staying overnight in Ashburton, then three nights in Greymouth, while taking day trips to Westport, Hokitika and via coach to the Denniston Plateau.
The train would then cross back over the Southern Alps, stopping for the night in Ashburton before returning to Dunedin on September 12.
Mr Bond said the trip would capitalise on railway nostalgia and interest in longer excursions.
The trip was part of a new growth strategy introduced since the Dunedin City Council-owned company rebranded as Dunedin Railways last year.
The company leased the Silver Fern railcar, which could be used on tracks around the South Island, and was looking for ways to fill quieter winter months between cruise ship and summer tourist seasons, he said.
That had already resulted in new trips to Waitati, Moeraki and Oamaru, as well as one-off trips to destinations including Bluff, he said.
More trips to destinations ''up the coal line'', including Nightcaps in Southland, could follow.
The company was attracting an increasing number of private charters, including a North Island company which hired the Silver Fern on a trip from Picton to Invercargill, he said.
A Christchurch law firm was also looking to charter the Silver Fern later this year, and a Chinese tour group used it for a one-way trip to Palmerston yesterday, he said.
The charter market, in particular, represented a new opportunity to bring money into Dunedin, he said.
The interest had helped fuel overall growth of about 5% in the past year, rising to 7% if the ''fickle'' cruise ship market was excluded.
That was still below the 10% annual growth between 2000 and 2006-07, but there were hopes those levels could return, he said.
He ruled out reintroducing a regular suburban commuter service in Dunedin.
