The NSW government will establish a 500-hectare national park in western Sydney - the largest in the area in more than a decade.
The site at Shanes Park, between Penrith in western Sydney and Windsor in the city's northwest, will be ready for the public by 2023.
The national park will be a feral-free area and the government says it wants locally extinct species to be reintroduced in the sanctuary, including quolls, brush-tailed phascogale and bettongs.
Emus and koalas will also be reintroduced to the area.
Some 30 species will be returned to the parkland, which is yet to be named. Specialist perimeter fencing will enclose the site.
Environment Minister Matt Kean says the feral-free area across NSW's national parks will soon stretch to almost 65,000 hectares, with a 40,000-hectare site near Cobar currently under construction.
"We're announcing our very own Noah's Ark," Mr Kean said on Sunday.
"There will be boardwalks and walking trails and we will be making this a special place for not only western Sydney but everyone across NSW who cares about our natural environment and native animals."
Premier Gladys Berejiklian also welcomed the announcement, saying the COVID pandemic had illustrated the importance of open public spaces to residents' physical and mental health.