Dunedin and Queenstown are considering a joint bid to host the World Masters Games in 2017.
Up to 25,000 competitors - most from outside the two centres - would be expected to take part.
New Zealand Master Games director John Bezett, a Dunedin city councillor and chairman of the Dunedin Masters Games, confirmed the move.
He said a joint bid involving Dunedin and Queenstown would be attractive when measured against New Zealand's other major centres.
Hosting the international event could cost millions, likely to be paid by local authorities and central Government, but could bring with it "huge economic benefits".
The stumbling block could prove to be a lack of suitable accommodation in Dunedin.
To accommodate the influx of athletes, their families and supporters, the event would need to be staged in February, when Dunedin's student halls were available to be used for visitor accommodation, Mr Bezett said.
Consideration was also being given to other measures, including a special shuttle service - by aircraft or road - transporting people to beds in Queenstown and as far away as Christchurch, he said.
It was an option also being considered to accommodate visitors during the Rugby World Cup in 2011, he said.
The joint Dunedin/Queenstown bid would be among the frontrunners in New Zealand to stage the Games, which Mr Bezett believed were best suited to a "medium-sized city" with good facilities and accommodation.
Dunedin would have the facilities, capped by the construction of the Forsyth Barr Stadium, and the pull of Queenstown would "add a flavour I think international competitors would really appreciate", he said.
"Where we don't match up with other cities is in our level of accommodation.
If we bring Queenstown into the equation then we have got the accommodation, but then we have got the difficulty of moving between Queenstown and Dunedin."
Events would be divided between the two centres, starting in Queenstown before switching to Dunedin.
A multi-day endurance event from Queenstown, through Central Otago to Dunedin, could provide a link between the two, he said.
About 11,000 athletes from around New Zealand - about half of them from Otago - could be expected.
The rest would be international competitors, about half coming from Australia, he said.
"Dunedin and Queenstown would be a very attractive proposition for people coming from overseas.
It's one of the very good reasons we could have an opportunity of getting the Games.
"It's quite able to be managed but we need to talk about a lot of things," he said.
New Zealand Masters Games officials had received encouragement to make a bid from Sport and Recreation New Zealand (Sparc), Mr Bezett said.
A New Zealand Masters Games delegation, also including Dunedin City Council chief executive Jim Harland, planned to meet World Masters Games officials during next month's Games in Sydney, he said.
The event was staged every four years, switching between the northern and southern hemispheres, and at the completion of the Sydney Games was next due south of the equator in 2017, he said.
Australia has already staged the event three times, and South Africa once.
A feasibility study had confirmed the "huge economic benefit" of hosting the event, although the details could not yet be released, he said.
If a decision was made to bid for the event, the New Zealand Masters Games would invite applications from New Zealand centres to stage the event, with the best put forward to World Masters Games officials.
"There are a number of issues we have to resolve and one of them is cost. What we are going to have to come up with up-front to stage the games?
"World Masters Games have a start-up fee and it's quite substantial. We are talking millions."
The cost likely would be shared by the local authorities involved in hosting the event and central government, he said.
