Paul Keating stands like a king surveying the headland park at Barangaroo.

As prime minister he may have failed in his quest to bury the ugly Cahill Expressway at Circular Quay, but his latest project, the headland park at Barangaroo, will stand as a monument to his single-minded determination to recreate the original headland, which was destroyed 100 years ago by maritime development at Darling Harbour.

The new headland park will be opened on Saturday morning by Premier Mike Baird with Keating by his side. Many people have contributed to the park, but it was Paul Keating who pushed, demanded, cajoled, badgered and insisted that instead of preserving the archaeological heritage of Sydney's docklands, we should look further back to the time of settlement.

Keating's vision was to return the area, known in the colony as Millers Point, to "a naturalistic park", which would complement the other four headlands in the western harbour: Balls Head, Ballast Point, Balmain and Blues Point.

The result is a park that Sydney can be proud of. The new foreshore is constructed of 9600 blocks of golden Sydney sandstone hewn from the site. Terraces of juvenile angophoras, Port Jackson figs, banksia, lomandra​ and hardenbergia​ rise up to the crest of the hill, where one can survey a vista of the western harbour largely hidden from Sydneysiders for 100 years.

"The Harbour Bridge is like a curtain that has divided the harbour into two," Keating says. "There was the beautiful wide harbour and the ugly, old industrial western harbour. But the more intimate western harbour was where Sydney's original inhabitants lived."

Keating refers to the "constellation of green headlands" that reach out gently towards Memel​ (Aboriginal for "eye", and better known to Sydneysiders as Goat Island). It sits just 500 metres from Barangaroo, an easy paddle for the first inhabitants.

The diaries of Lieutenant-Governor David Collins, published in 1798, record that Bennelong said the island "was his own property, that it was his father's". Bennelong appeared to be "much attached" to Memel and was often seen there with his wife, Barangaroo.

Under Keating's grand vision, Goat Island should be returned under native title to the original owners, and most of the remnant buildings removed.

The headland park has had many midwives: American landscape architect Peter Walker, teams of architects, former head of the Barangaroo Delivery Authority John Tabart, former planning minister Frank Sartor, and successive premiers.

But none can lay claim to having had Paul Keating's single-minded purpose.

As chairman of the design excellence review panel for the massive Barangaroo project from 2005 to 2011, Keating was involved in choosing the winning design, led by Philip Thalis​. He was also instrumental in recommending that elements of another consortium's design be incorporated.

This included a headland park, the two coves that punctuate the site, and a city beach (which never went ahead), returning it to a closer approximation of "the typology of Sydney Harbour".

His vision set Keating on a collision course with Thalis, whose design referenced the maritime heritage of the site.

"What they had was this view called archaeological determinism – that we had lost what was there and we should just suck it up," he says.

"Why would you want to keep a concrete slab that looks like an aircraft carrier?" he asks, disdainfully.

Behind the scenes, Keating lobbied for the inclusion of his vision for a naturalistic headland.

After Morris Iemma became premier, Keating met him in June 2008 armed with a hand-drawn sketch of his scheme for the park and a more natural foreshore. He still has that drawing.

"A headland has to have water on both sides. That's why we had to have the northern bay. For the first time in over 100 years, you will see the harbour from Hickson Road," he says, proudly.

Barangaroo has gone through many changes, most of which have involved higher buildings and more density.

There are still threats to the Keating vision, not least of which is the pressure to allow greater height and floor space in Central Barangaroo, which adjoins the park.

He also worries about the casino and hotel tower proposed by James Packer's Crown Resorts. Keating doesn't mind the height but would prefer it to be located alongside Hickson Road, instead of close to the water's edge.

As we enter the park with Keating as our tour guide, he curses the concrete entrance to the carpark.

"Why couldn't they face it with sandstone, Why couldn't they cover over the driveway and link it to Munns Park?" he asks in exasperation.  "They are just so mean."

But by and large, he is happy.

"This could never have come out of the planning process," he says. "In the end I won, but only through horsepower."