The Australian-made Sunliner caravans have been described as "jelly beans", "baked beans" and "like a little adult cubbyhouse" and have, quite literally, become icons of the highway, where their distinctive shape is used as the universal symbol for caravans on Australian road signs.

Owners of the vintage caravans are often also devout fans and on Father's Day weekend, a gathering of the van owners marked its 60th anniversary with a celebration in New South Wales mid-north coast twin towns of Forster-Tuncurry.

More than 30 of the Sunliner caravans rolled in for the event which marked 60 years since Bert Tickner manufactured the first Sunliner, which was Australia's first fibreglass caravan.

More than 30 Sunliner caravans made the trip to the birthplace of the vintage van. ( Supplied: Murray Plaister )

Queenslander Kim Bayne, who owns three unrestored Sunliners, organised the milestone event, which included the cutting of a cake and a display of the vans in John Wright Park in Tuncurry.

A local icon

Walter and Adrienne Hacene, from Wootton near Taree, feel very lucky to live near where more than 500 of the Sunliners were manufactured between 1958 and 1966.

"There's more Sunliners around the Forster area than probably other places in Australia," Mr Hacene said.

"Because I work for myself on different properties around the place, I've managed to stumble across a few in very derelict condition and managed to talk the people into selling it to me."

Sunliner caravans take over the Forster-Tuncurry Bridge on the NSW Mid North Coast as part of the 60th anniversary celebration ( Supplied: Daisy & the Duke Photography )

He said that the van's increasing popularity meant that they were becoming harder to find.

"I think the cat is out of the bag now and everybody is after one because they look so good behind old cars and they're light to tow," Mr Hacene said.

"So they're becoming very popular and harder to find."

Ms Hacene pointed out that on road signs indicating nearby caravan park the shape of a Sunliner is used as the caravan icon.

"The blue signs on the side of the highway that you see — that's the typical Sunliner shape," she said.

"And when I was growing up we used to see them around and we used to call them jellybeans or baked beans."

"Everybody that hops into it instantly smiles because of the yellow colours and everything," Walter Hacene said. ( ABC News: Luisa Rubbo )

Ms Hacene said she and her husband are addicted to collecting the small vintage vans.

"It's a disease — it is an illness," she said.

"Once you have one van you can't stop at one. They're just our happy place.

"We actually come and sit in it at home, have pizza and a couple of wines. It's just like a little adult cubbyhouse."

Part of Australian history

Mr Tickner's son Robert, who grew up around the caravan factory and remembers going there every day after school, came along to the 60th celebration.

"It was a very ambitious project to launch a substantial manufacturing business, but my father was a passionate believer in decentralisation policies and supporting his local community," he said.

Robert Tickner's father "left school at 13, was a very intelligent person and most of his skills were self taught. He was always inventing new things in his workshop at the back of our home in Lake Street, Forster." ( Supplied: Robert Tickner )

"There was a substantial workforce. I think it was over 40 at one time, who worked hard to build a quality caravan which has survived 60 years and is still going strong, as I was reminded by the gathering.

"I think people have come to love the iconic Sunliner Caravans and see it as a little part of Australian history, which still inspires people."

Claude Harris bought his caravan in 1970 and "just kept it and kept it in its very original condition as it was when it came out of the factory in 1966." ( ABC News: Luisa Rubbo )

Still going strong

Claude Harris, aged in his 90s, bought his Sunliner caravan in 1970 from "a high-pressure salesman in Kiama" on the NSW South Coast.

"This one's around about number 580 and this could possibly be the last one or at least one of the last ones out of the factory." said Claude's son Ross. ( ABC News: Luisa Rubbo )

Mr Harris, from Albion Park, has kept the van in its original condition.

"Dad put a three-way fridge in it," Claude's son Ross said of his father's upgrades. ( ABC News: Luisa Rubbo )

His son Ross said the only thing that had been changed in his dad's van was the fridge.

"It originally had an icebox in it, where you used to have to go into town and get ice from the ice works, and of course when they disappeared getting block ice was almost impossible — and party ice melts in the summertime, so dad put a three-way fridge in it," he said.

Mr Harris said the current popularity of vintage caravans has increased the popularity of Sunliners.

"They're usually grabbed fairly quickly when they come up for sale," he said.

"There's a big cult following in retro, vintage vans these days, but the big advantage of the Sunliners is that they are so light.

"Everything about the Sunliner is just right.

"This one you pull up, plug the power in, make a cup of tea and you're finished."

Monica Squires and her husband Shaun, from Shellharbour, made the trip in their painted pink and white 1960 Sunliner.

"It's lightweight, it's cute, it looks like a little egg, it's comfortable. It's very, very easy to tow. We love it," said Monica Squires from Shellharbour, NSW. ( ABC News: Luisa Rubbo )

"We did paint it pink to match our LJ Torana — so that's an original Strike Me Pink," Ms Squires said.

"I'm very lucky that my husband doesn't mind sleeping in here cause it is very girly.

"A lot of the times we go caravanning we're the only vintage one there and you arrive, you open the door and everyone's crowding around to see you which is nice."