A 6km bike and pedestrian road that will run along the 100-year-old rail corridor and connect Sydney's two most popular water trails will open later this year.

The Minnesota government said Friday that the Greenway - from Earl Wood's Cooks River north to the inside of the Cooks River, the bay running on the Parramatta River in Iron Bay - has been 80%.

The $60 million project will intersect the Southwest Metro Line and will be completed in 2026.

NSW Prime Minister Chris Minns said both projects would “change transportation within the city” and unite communities that previously lacked connections through walking, cycling or public transport.

“This project is limited to the internal, but if you link those two parts… you’ll see a lot of Sidnesi people with the inner western, Canterbury area and then all the way to the city,” Minns said Friday.

“We think this road will be a major tourism attraction, not only for locals living in Sydney, but for people from all over the world. In this great city, it’s an extra thing, the government is very clear that we intend to have more urbanization consolidation (and) more density.”

The project follows the internal western light rail and Hawthorne Canal routes and requires the construction of underground passages and tunnels under the main roads to create continuous paths.

The Hercules Parklands and New Canterbury Road underground passage are the final parts to be completed.

Local Councilman Jo Haylen said the "active transport" corridor connects the Cooks River in the south to the ports in the north. The greenway will allow people to access the subway at Dwyxishan Station.

The completed project will feature a park and front hole, playground, sports facilities, jungle venues, public art, cafes, and cultural and historical sites.

The Minnesota government's housing policy focuses on increasing the density of housing stocks around urban centers and transport.

Minnes said Friday that it needs to take the "best practice in the world" approach to achieve "the kind of density and livability you see in places like Brooklyn, London, Barcelona and Paris".

“There is absolutely no reason why we can’t let people live in a narrow community with world-class public transportation, ride in bike paths, wonderful, beautiful, open parks and enjoy the most beautiful city in the world,” he said.

The original idea for Greenway came from community advocates inside.

Interior Western Council mayor Darcy Byrne said it was a 20-year vision for the local community. He said the “incredibly exciting” project will change the way people move.

"We know that kids will use the greenway to go to school, walk or bike, and families will use it in recreation and that will also become a hub for public art," he said.

“We are investing in 10 major public art along the length of the greenway, which will make this a place that people from all over Sydney want to visit.”

Darcy added: "At a moment... the subway will open and there will be a very fast railroad run every four minutes. It will be a real change. It will take people off the car, head to their scooters and bikes, and go more."