Cataclysmic events of 100 years ago marked

The strains of the Last Post echoed through the cold winter dusk and the first of more than 60,000 names was projected on the nation's commemorative halls.

Australia will not forget.

Remembering the sacrifice, the fear, the patriotism and the tragedy of World War I will continue to shape Australia's future, Prime Minister Tony Abbott said on Monday.

It was important contemporary Australians knew what went through the minds of those who enlisted, including feelings of adventure, fear, excitement, mateship and love of empire.

"It was a terrible war. In one sense a tragic waste but it was for a good cause," Mr Abbott told a gathering at the Australian War Memorial in Canberra to mark 100 years since the start of the war.

"The war shaped our country and our reflection on it will help to shape our future."

Veterans affairs minister Michael Ronaldson said the loss of more than 60,000 young men devastated Australia for a generation.

"Today marks the beginning of our nation's four year commemoration of these cataclysmic events," he said at the War Memorial's Last Post ceremony.

Senator Ronaldson and other political and military dignitaries laid wreaths in the evening, followed by the diplomatic corps in an event symbolising the world's unified desire for peace.

The gathered crowd heard the story of Captain Keith Heritage, the first Australian to enlist after WWI began.

For the next four years, the names of those killed in action will be projected on the memorial's Hall of Memory, which houses the tomb of the unknown soldier.

Australian school children have produced an audio installation, reading through the names and ages of all those on the honour roll.

Memorial director Brendan Nelson said these were just the start of a four-year program to ensure every Australian never forgot the individual sacrifices made in our name.

Commemorative events were held around the country on Monday.

The Perth Mint unveiled a series of limited edition coins telling the story of Australia's involvement in World War I, to be released over the next five years.

Meanwhile, NSW Premier Mike Baird announced the Anzac Memorial at Sydney's Hyde Park will finally get its water feature - more than 80 years after its completion.