A suburb of 10,000 people could be built on Canberra's racecourse, putting every resident within a 10-minute walk of a light rail stop, the ACT Greens say, unveiling a plan that could end horse racing in the territory.
The Greens said they were open to a compulsory acquisition of the Thoroughbred Park site, which could leave Canberra without a horse racing track.
Greens leader Shane Rattenbury said the concept plans commissioned by the party set out a vision for the site that included direct investment in public housing and public transport.
"Land is the most precious resource we have in the ACT and we need to use it carefully to maximise community benefit," Mr Rattenbury said.
"But right now, horses have their own light rail stop while there's a desperate need for homes in central areas."
The Greens' Jo Clay said the first step to redeveloping the site needed to involve Canberrans deciding what needed to be built.
"Do we want a racetrack with luxury apartments on the side, or do we want a whole vibrant precinct with schools, community facilities, nature spaces - right on light rail?" Ms Clay said.
Labor and the Greens, the parties which govern together, clash over providing government support to the horse racing industry under a deal in place until June 2027. The Greens are opposed to providing public money to the industry.
But Ms Clay said the party could work with Labor on its plan for the racecourse.
"I'm confident that when we put up a really good idea, that is clearly the direction we need to take for the future of Canberra, that we will be able to negotiate and get that in place," she said.
The Canberra Racing Club has sought a Territory Plan Variation to sell unused land around the racetrack in Lyneham to develop housing close to the light rail network.
The club hopes the rezoning process will be finished by the end of the year to allow the $2 billion redevelopment process to proceed.
Mr Rattenbury said Labor and the Liberals would be content with the racing industry making a profit from luxury properties on the site, but the Greens wanted to deliver "maximum community benefit".
The Greens have previously indicated their interest in turning the entire site into housing, which is leased to the racing club until at least 2100.
Planning Minister Chris Steel in January criticised the Greens for floating the idea of a housing-only redevelopment for the racecourse land without consulting Labor or the racing club.
"The Greens know that more housing can be accommodated on the existing site and include the club. It's not a binary choice," Mr Steel said at the time.
The Greens concept master plan for the land, between the Barton Highway, Northbourne Avenue and Flemington Road, included up to 5000 medium-density homes, 540 of which, the party said, would be publicly owned.
The site, where a racecourse opened in November 1962, could also host a retirement village and a new preschool to year 10 school, along with a health facility, community hall and town square.
The concept plans showed streets designed to meet the needs of pedestrians and would also include shared parks, shops, restaurants and offices.
Ms Clay, the Greens member for Ginninderra, said the major site needed to be developed in the interests of Canberrans.
"We'd be happy to negotiate with the horse racing industry, but we'd be prepared to compulsorily acquire the land on just terms," Ms Clay said.
Asked whether those negotiations would involve identifying a new racecourse site in the ACT, Ms Clay said she could not see the need for two racetracks within 20 kilometres of each other.
"There's already a racetrack out in Queanbeyan. But obviously a just terms acquisition would probably involve some kind of payment and that would help this dying industry work out what their next steps are," she said.
Ms Clay said she did not imagine the Canberra Racing Club would be surprised by the Greens proposal.
"I also think it shouldn't be a shock that when government is looking at a major site so close to Canberra that it will look at a number of options and that it will not simply respond to one option put up by the racing industry or by one property developer," she said.
