The vision, now open for public comment, will be overseen by a new NSW government agency that brings together various park trusts and other key sites.

Callan Park in Sydney's inner west is the first park identified by the agency for $10 million worth of urgent restorative work and follows lobbying and a petition from concerned community residents and local Inner West Council.

"This investment in Callan Park is just the start and demonstrates our commitment to revitalising and growing our city's great public open spaces, starting with one of its great forgotten jewels," NSW Planning Minister Rob Stokes said in a statement on Friday.

The agency will look after more than 6000 hectares of parklands across Sydney.

"In the past, the individual parkland trusts have had a sole focus on the land within their boundaries," Mr Stokes said.

"Now we have a once-in-a-generation opportunity to look beyond those boundaries to plan for our parklands and open spaces over the next 50 years as a connected and vital network that forms the backbone of our city."

The 60-hectare hertage-listed Callan Park in Sydney's inner west has been the subject of an ongoing campaign from local groups, including Friends of Callan Park, who feared the site would be sold off to developers.

"This investment in Callan Park is just the start and demonstrates our commitment to revitalising and growing our city's great public open spaces, starting with one of its great forgotten jewels," Mr Stokes said.

Australian Associated Press