Those with vivid memories of Gough Whitlam's dramatic dismissal by governor-general Sir John Kerr in 1975 have arrived at Old Parliament House to express their condolences, after his children released a statement on Tuesday announcing his death at 98.

As many paused to lay flowers and sign a condolence book, tours of school children climbed the famous front steps and passed through the halls for another recital of Australian history.

One visitor who signed the condolence book was Hugh Ford, whose father John was Whitlam's press secretary for a nine month period before the dismissal.

"He was a real inspiration to me and I really looked up to him," he said. "The reason I studied law was because of him and it's a really sad day for Australia to lose such a man."

Mr Ford said he remembered his father speaking fondly of Whitlam and describing him as " a man who would decide what the right thing to do was rather than the politically expedient thing".

Some of the younger visitors who signed the condolence book knew little of Whitlam but recognised his historical importance.

Will Duff, an 11-year-old tourist from Perth who spends his afternoons watching question time, had come to Old Parliament House to "see the room where politicians argue" and learn more about Australian political history.

His parents and grandparents took time to share their own memories of Whitlam as he walked through the former House of Representatives.

Michael Evans, the manager of content at the Museum of Democracy, said Whitlam's legacy would be interpreted differently by new generations of Australians as more time passes from his dismissal.

"Until fairly recently, the vast majority of people who came to Old Parliament House were worried about the dismissal and Whitlam will always remembered as the main figure in that event," he said.

"In recent years that's started to change slightly and probably increasingly people are now starting to think about what Whitlam's legacy was.

"Whitlam's legacy is starting to be seen in a more balanced way with a focus not just on the dismissal but also on what he achieved, what he didn't achieve and what he could have achieved.

Sitting quietly in an upstairs Senate room was Michael Northcott, a man who remembered the dismissal as the defining aspect of Whitlam's legacy.

"I remember it like it was yesterday," he said.

"I saw it on the news and read about in the papers and unfortunately for him that's one of the key things that he will be remembered for."

Staff at Old Parliament House are expecting more visitors to arrive during the day to sign the condolence book and to lay flowers on the front steps, where he posed famously after being dismissed.

ACT Chief Minister Katy Gallagher offered condolences to Mr Whitlam's family, calling him a "legendary Labor figure".

"Gough Whitlam was a great reformer and an inspiring leader, who leaves a remarkable legacy.

"[He] was a statesman who changed our country for the better and set a high standard for all of us in public life, not just those on the progressive side of politics," Ms Gallagher said.

"He led our nation at a time of great change and wasted no time in making his mark on Australia."