Residents in the Ormeau area of south Belfast met on Thursday night to oppose any plans for a new national stadium being built there.
The planned stadium would host soccer, GAA and rugby matches
Ormeau Park was one of three locations in Belfast suggested for the development.
One developer interested in building on the site said that local concerns were misplaced.
However, community group member Caroline Hughes said park users felt strongly about the issue.
"Myself and a few other park users - who do not know each other - met up in the park one day and were discussing the issue and we all realised that we were all opposed to it and we all felt powerless as individuals.
"So we thought we'd come together and form a group and try and save Ormeau Park from the developers," she said.
However, Peter Holmes, of the Sheridan Group, one of two consortiums with proposals for Ormeau Park, said the stadium plan would preserve much of it.
He said the stadium would be built where tennis courts and football pitches currently were and treelined areas would remain.
Paul Durnian, of City of Belfast Stadium, the other consortium in the running, said not one tree in the park would be removed.
He said very strict criteria had to be met to develop the site and it would be "sympathetic to the park and also to the local community".
Plans have been drawn up for a 35,000-seater facility at the Maze site, near Lisburn in County Antrim.
However, there have been repeated calls for the new stadium to be built in Belfast.