SHE has battled extinction more than once but now, ahead of her 150th birthday, Glengallan Homestead has arguably never looked so good.

The building survived abandonment in the 1920s, threats of dismantling in the post-war years and then near-dereliction to be reborn at the turn of this century into a thriving business.

Prime Minister Malcolm Turnbull has sent his best wishes as the historic icon prepares for a weekend of grand celebration.

This weekend a lavish dinner will take place at the restored house for 185 guests as a symbolic celebration of the building's survival.

The homestead, which dates back to 1867, was inhabited by four families over the years through to 1927, when it was abandoned.

After years of neglect, the house fell into ruin before being purchased by Wally Leggett and the Glengallan Homestead Trust in 1993.

Years of painstaking work was done to restore the house and the property.

In 2002 the house was opened to the public as an important Southern Downs heritage tourism operation.

Glengallan Homestead Trust chair Donna Fraser said guests from Melbourne to Mackay were attending the dinner. "Descendants from four of the owner/residents families are coming," Mrs Fraser said.

"The Marshall, Deuchar, Slade and Gillespie families will all be represented, which is wonderful for the occasion."

Mrs Fraser said the night would be a celebration of 150 years of history but also acknowledgement of all the work and commitment that has gone into making the homestead what it is today.

"Family of Wally Leggett will also be here, who was instrumental is recognising the significance of the property and purchasing the five acres to develop a heritage precinct at the house," she said.

"I think it's a great tribute to the project, that these people want to be here to celebrate with us.

"And it's not only the 150th birthday of the house but it's also 15 years since the heritage tourism operation began."

Mrs Fraser said the guest list was a representation of not only the past and the house, but also the restoration project and the future of Glengallan as a heritage tourism icon for the region.

Hard work and determination

A SMALL but committed team of board members and volunteers have turned Glengallan Homestead from a teetering ruin into a successful tourism operation over the past 15 years.

Today, the Glengallan Heritage Trust sustains two full time positions, a heritage centre and a site manager, as well as two weekend casuals who run the busy cafe.

The heritage tourist destination sees more than 10,000 visitors pass through its doors each year.

Board chair Donna Fraser said the not-for-profit organisation was run as a business by experienced business people.

"We understand what it takes to keep a business viable and I think that expertise is why it's been a success," she said.

"Anything we make from entry fees, profits from our markets, events and grants gets ploughed back into the cost of running and maintenance of this grand home. Insurance, painting, general repairs, staff wages, there are a lot of expenses and not much left over."

Trust treasurer Col Smith said he had seen many heritage sites all over the world.

"Australia is a young country and we need to preserve our heritage sites for future generations," he said. "The story of Glengallan is thanks to the determination and in-kind support from many people, and we're proud to still be operating under our own steam."