Prime Minister Stephen Harper praised Canada as a leader on the world's stage as thousands of revellers gathered on Parliament Hill in Ottawa to mark the nation's birthday.

"A country first inhabited by our indigenous peoples built through historic compromise between the English and French and populated by waves and waves of immigrants from around the world," Harper said in his message Saturday, speaking to a sea of red and white.

"Today, Canada is a leader. Our businesses, our athletes, our artists, musicians and writers, all excel on the world stage and our country leads by example, standing up for the values that make Canada great -- helping to ensure the spread of freedom, democracy and the rule of law around the world."

The prime minister called on Canadians to show their appreciation to "those who do it best for us in Afghanistan and around the world," listing the envoys, development workers and troops who are stationed abroad.

Earlier, the 21-gun salute was fired by the 30th Field Regiment in Ottawa, said CTV's Roger Smith.

Master Bombardier Bounyarat Tanaphon Makthepharak, the Canadian soldier who was critically wounded in a rocket attack on the coalition base in Afghanistan on Friday, belongs to the same regiment.

As is tradition, one of the biggest Canada Day celebrations is on Parliament Hill, where a show of music and dance will culminate after sunset, with bursts of fireworks over the Peace Tower.

Meanwhile, Gov. Gen. Michaelle Jean urged Canadians not to take their gifts for granted on the day of their nation's birth.

"Dear friends, let us rejoice in our good fortune, in a world where too many people are still struggling with thirst, hunger, misery and violence every day," she said.

"Let us never taken our blessings for granted out of consideration for those who have been so cruelly deprived."

The first order of the day for Harper and Jean was to attend a wreath-laying ceremony honouring First World War Veterans.

The ceremony at the National War Memorial marked the 90th anniversary of the battles of the Somme and Beaumont-Hamel.

The First World War Battle of Beaumont-Hamel was at the beginning of the Battle of the Somme, on July 1, 1916.

About 780 men from the First Newfoundland Regiment were part of a British contingent that took part in the advance. Only about 110 Newfoundlanders survived unscathed.

The street in front of the Hill was also joined by protesting farmers who are aiming to pressure the government to live up to its farming promises.

The group Farmers Feed Cities is calling on the government to accelerate its planned $775-million aid package for farmers.

Though the group's main objective is to air its concerns, they are also aiming to educate people on the importance of protecting the nation's food supply.

The protesters were to give away 34,000 cups of ice cream and thousands of cheese curd samples.

The Canada Day tradition marks the signing of the British North America act on July 1, 1867, when the first colonies were united to become the Dominion of Canada.

The tradition of a single, huge national celebration in Ottawa was established in the late 1950s, with a routine involving a day of Parliament Hill ceremonies followed by a mass band concert and fireworks display.

More than two decades later, the approach was changed to encourage local celebrations in communities countrywide.

In 1982, July 1, which was known as "Dominion Day," became "Canada Day," marking another step away from the nation's colonial past.