In his address at the Australian War Memorial, Victoria Cross recipient Corporal Mark Donaldson, who served in Afghanistan, paid tribute to the men and women who served across multiple decades and multiple conflicts.

"Perhaps it is the capacity of ordinary humans to do extraordinary things when coupled with extreme circumstances," he said.

"To fight harder, to march further, dig deeper, move despite overwhelming odds and care for wounded mates."

More than 35,000 people attended the service, with large crowds stretching down Anzac Parade.

Among them was Conder resident John Rixson, who served as part of a UN peacekeeping task force in Cambodia, who was at the service with his wife Hazel and grandson Ryeece, who was wearing his great-grandfather's war medals from World War II.

He said the family came to the dawn service every year, and said the day was about respect.

"People come here for different reasons, but for me, it's about respect for those who have served," Mr Rixson said.

"Other people come because there's a connection here with an older Australia, because Australia has changed in the years since major conflicts."

Chief Petty Officer William Edmondston attended his first dawn service at the war memorial since moving to Canberra from Sydney.

Chief Petty Officer Edmondston had served in the navy for 32 years, and said Anzac Day was about honouring those who had served before him.

"It's definitely different coming to the dawn service in Canberra and seeing something like this," Chief Petty Officer Edmondston said.

"Normally there's a few thousand people crammed into Martin Place for the Sydney dawn service, but here you get all these thousands in all this open area."

Before the service began, excerpts of diaries and letters written by Australians who had served in war were read out by current service men and women.

Images of those who served in the military since the Boer War were projected onto the walls of the war memorial, with the final images focusing on contemporary conflicts and athletes from the army, navy and air force who competed at the Invictus Games held in Sydney last year.

Lights were dimmed from 5.15am, with the silence along Anzac Parade first broken by the sound of a snare drum and the catafalque party.

A didgeridoo was played by Wing Commander Jonathan Lilley, before the service began.

Corporal Donaldson said in his address the actions of past and current would always be honoured at the site of the war memorial.

"This place reminds those who wear our uniform that we care; that we are grateful for their sacrifice above self; that we have a place to reflect and that we will never forget," he said.

A decade ago, Corporal Mark Donaldson became the first recipient of the Victoria Cross in more than 40 years.

That honour came a few months after he rescued a coalition forces interpreter from heavy fire in Oruzgan Province in Afghanistan.

But at the Anzac Day dawn service, it was the sacrifices of others of which he spoke.

Those included the actions of oldest living Victoria Cross recipient, Keith Payne, aged 85.

He received the honour for rescuing fellow soldiers while under enemy fire and suffering his own injuries during the Battle of Ben Het in 1969.

Corporal Donaldson said all Australians had an obligation to such people.

"We honour their sacrifice by living a good life in support of others, respecting the freedoms given us and inspiring others to build a better Australia and a stronger Anzac spirit," he told a crowd of thousands of people.

"We should strive to be worthy of these sacrifices made for us."

Speaking after the service, the Australian War Memorial director Brendan Nelson said days such as Anzac Day brought Australians together.

"Today, 35,000 people gathered in the pre-dawn darkness 104 years after the Gallipoli landings to recommit ourselves to one another, our nation and the ideals of mankind, to be reminded of the ties that bind us as Australians," Dr Nelson said.

"It's a chance to pay respect to the millions of Australians who have worn the uniforms of the army, navy and air force and to be reminded of the sacrifice made."