One of Sydney's prominent recreational sites has had a $9m sustainability facelift, creating a new green oasis in the city.

The transformation of Prince Alfred Park, which dates back to 1865, is the first extensive upgrade of the 7.5 hectare Surry Hills landmark in more than 50 years.

Hundreds of new trees and plants are now flourishing in the park including rainforest species, succulents, shrubs and grasses, some of which have been planted to naturally filter water and interpret a former creek bed.

Other parts of the park feature citrus trees, figs and native palm trees, while passionfruit vines and climbing frangipanis have been planted to grow over the outer edges of five new tennis courts in the park.

An extensive meadow of locally occurring groundcovers and grasses has been planted as a potential fauna habitat. The meadow presents a striking contrast to Victorian themed plants.

New energy-efficient lighting that is better for the environment, reduces power costs and increases safety has also been installed throughout Prince Alfred Park.

"We've installed an underground stormwater re-use system that will supply 95 per cent of the park's water needs," said Lord Mayor Clover Moore MP.

"By capturing the run-off from streets in an eight-hectare area surrounding the park, we will save millions of litres of water and contribute significantly to the city's water savings targets."

"Sustainable lighting, a new water recycling scheme and down the track, localised energy generation, will help make our park more sustainable for generations to come.”

The upgrade of Prince Alfred Park also includes:

Five new tennis courts with the same "plexi-cushion" surface used in Flinders Park, the home of the Australian Open

A new exercise circuit with three fitness stations linked by connected accessible paths for joggers, pedestrians, bikes, prams and wheelchairs

A themed children's area with custom designed and handmade play equipment

Two new basketball courts and an additional half-court overlooking the rail line and city skyline

New BBQs and family picnic areas with custom-designed tables and seating.

The next stages of the Prince Alfred Park project include an $18 million dollar refurbishment of the existing pool with new temperature-controlling and shaded landscaped sunbathing areas, along with the $2.8 million refurbishment of the historic Coronation Centre into a community facility.

Prince Alfred Park was first established in 1865 and was named after Queen Victoria's second son when he visited Sydney. The Park has an extensive history and was home to the Heritage-listed first Agricultural Society show in 1869, and a celebration the following year to mark the centenary of Captain Cook's landing at Botany Bay.