After all, his seven-year-old daughter, Joanne, was given the honour of launching the Sydney harbour ferry at the Tomago yard.

"It was just the excitement, and the fact that my daughter was doing it," Mr Allen recalled from his Sydney home.

"She was the last 'Lady' ferry built by Carrington Slipways."

Lady Northcott is back in the waters of its birth.

For more than nine months, the vessel and another Sydney ferry, Lady Herron, have been berthed in Newcastle harbour.

For Lady Herron, this has also been a homecoming of sorts. The ferry was built at the State Dockyard and launched in 1979.

Both vessels represent the end of an era, as they are the last of the "Lady class" ferries, named after the wives of NSW governors.

"They were iconic," said Mr Allen of the ferries.

"We've had Lady class ferries since the late 1800s, when they were introduced by the Balmain New Ferry Company."

Bill Allen said Lady Northcott was a versatile ferry, providing services on both the inner and outer parts of Sydney harbour, carrying passengers to and from Mosman and Taronga Zoo, but also able to do the Manly run, riding the swell coming in through Sydney Heads.

Lady Herron was a "real inner harbour ferry", mainly on the Mosman, zoo and Neutral Bay routes. The ferries were double-ended, meaning they could pull into or out of a berth without needing to be turned around.

Both vessels also participated in the Sydney harbour ferry races, which were started by Mr Allen. However, this chapter in Sydney harbour's history ended when both ferries were retired from service in 2017. The state government's Transport for NSW had said the ferries had reached the end of their working lives and were expensive to maintain.

The ferries didn't leave Sydney harbour without a fight on their behalf. A campaign to save the ferries was staged. One of the campaigners was high-profile artist Peter Kingston, who has depicted the Lady ferries.

"They are the harbour furniture," said Mr Kingston of the Sydney ferries. "They're the same as the cable cars in San Francisco.

"The loss of the Ladies on the iconic Taronga Zoo run is a great loss to Sydney and its harbour. The Ladies have character and grace."

The two Lady ferries arrived in Newcastle harbour in April and are tied up at an area known as the Snakepit, which is part of the Carrington shipyard run by Thales.

A spokesman for Thales said the organisation was "providing berthing space" for the two ferries.

Lady Northcott and Lady Herron have been sitting in Newcastle while their future is determined, with Transport for NSW looking at selling both ferries.

In a statement to the Newcastle Herald, a spokesperson for the agency said, "Transport for NSW engaged a maritime broker to explore the selling of the vessels, and we are still in the process of finalising our next steps. We will update the community when more information is available."

Peter Kingston is frustrated the ferries have been berthed for so long in Newcastle harbour without being used.

"Boats can't just sit there," the artist said.

Bill Allen, co-author of the book Waiting for the Ferry and the holder of an extensive collection of historical photos, said he hoped both vessels would find a new life carrying tourists, just as two other Lady ferries had been doing in Victoria.

"I'd like to see them live a bit longer somewhere else," Mr Allen said. "Wouldn't it be good to see the Ladies on Lake Macquarie?"

With debate having flared in the harbour city about replacing the famous Freshwater ferries on the Manly route, Peter Kingston proposed a return to the maritime past - bring these two Lady ferries back to Sydney.

"They're ready to roll," Mr Kingston said of the two ferries.

"If they [the government] are going to get rid of the Manly ferries, these Ladies could handle the swell [at Sydney Heads]."

Bill Allen said he understood that vessels had to be replaced - "I say to people, 'Would you fly to London in a 40-year-old plane?'".

But the historian suggested a new generation of the Lady class ferry, with improved technology, could be a way to keep afloat a quintessential Sydney harbour experience.

"I reckon the next iconic Manly ferries could be a whole lot of Lady Northcotts," Bill Allen said.

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