David Flint was 16-years-old when Queen Elizabeth II paid her first visit to Australia.
It was 1954, and the recently-crowned Queen accompanied by Prince Phillip sailed into Sydney Harbour after more than six weeks at sea.
Professor Flint, now the National Convenor of Australians for Constitutional Monarchy, said the public clamoured to meet the Queen.
"There was this enormous feeling of excitement and pleasure across the country," he said.
"Here was this young, beautiful woman and her handsome consort, coming to Australia. I think the country was absolutely united because there was very strong support for the royal family, particularly during the war.
"The king had been a symbol of resistance against Hitler and there was this feeling of here is the Queen, finally among us."
It was the first time a reigning monarch had set foot on Australian soil.
The Queen has since visited Australia another 15 times, opening the Opera House and the new Parliament House.
Now that she is the longest-reigning monarch in British history, republicans are using the milestone to call for the Queen to be the last non-Australian head of state.
Australian Republic Movement Chairman Peter FitzSimons said the country is ready to step away from the Commonwealth.
"We've got people across the political spectrum supporting us," he said.
"We're not arguing for revolution, we're arguing for revolution. We're saying, the time has come."
For life-long supporters such as Professor Flint, Queen Elizabeth's record-setting reign represents a key part of Australia's history and - he hopes - its future.
"She said that my whole life, whether it be long or short shall be dedicated to your service," he said.
"What she promised was service. That key, what she promised, was service and we see that now."
