OTTAWA - The Queen, one of the most enduring symbols of Canadian heritage, helped ring in the nation's 143rd birthday Thursday in a joyful bookend to the spirit of patriotism and community that coursed through the Vancouver Olympic Games.

She did not attend the 2010 Games in February, but what Queen Elizabeth and Prince Philip saw on the grounds of Parliament Hill would have given them a good idea of the atmosphere. Many of the gleeful 100,000 who gathered to celebrate Canada Day wore the red and white gear that was a uniform during those heady days of the Games.

The crowd roared when the Queen made an adroit reference to Canada winning the gold at the Games.

"As well as renewing a sense of common purpose within this country, the Olympics showed to others something of the extraordinary warmth and enthusiasm of the people as Canada welcomed participants and audiences from around the globe," she said in a speech. She was last on Parliament Hill in 1997.

"In many ways, Canada proudly affirms its place on the international scene, facing the future with confidence."

The Queen had arrived in an open, horse-drawn landau wearing a red chiffon dress with a diamond maple leaf brooch, and a white hat with red flower. Prime Minister Stephen Harper, wife Laureen, children Ben and Rachel, and Heritage Minister James Moore greeted her along the red carpet that snaked along her route.

To signal her presence, the 84-year-old monarch's own special flag was run up the Peace Tower, and a ear-splitting 21-gun salute began on one side of Parliament Hill.

She inspected a Guard of Honour dressed in their scarlet uniforms and bear skin hats, and listened to the Air Command Pipe and Drums as they marched past playing the Maple Leaf Forever. Nervous seven-year-old Katie Gibbons, wearing her orange brownie uniform and sash of hard-earned badges, handed the Queen a bouquet of flowers.

"It was really cool meeting the Queen," is what Gibbons said she would tell her friends.

Canadians from across the country, and visitors from much further afield, lined her route waving Canadian flags and shooting furious with their digital cameras and cellphones. Even a few vuvuzelas, the loud horns made famous during this year's World Cup of soccer, appeared on the Hill.

Sue Anderson of Ottawa had managed to get a front row vista, after helpful bystanders helped her hoist her wheelchair in place behind the barricades.

"I used to be a paramedic, and I was assigned to the Queen's ambulance in 1982 when she signed the Constitution," Anderson recalled. "We had to be out of sight so we didn't get to see anything, but Prince Philip came over with a flask and gave us all some tea. Isn't that exciting? It's time for us to watch this again, up close and personal."

The guests of honour took their seats atop the enormous main stage in front of the Peace Tower, one that had taken two weeks to set-up. It was more elaborate than usual, featuring multiple tiers and LED screens that flashed pictures and colours throughout the midday show.

Veteran actor Christopher Plummer, Hockey Night in Canada Ron MacLean and Quebec TV personality Genevieve Borne served as hosts of the show. Artists such as the Barenaked Ladies, Isabelle Boulay, and Johnny Reid performed for the royal couple and the enthusiastic crowd.

Harper thanked the Queen for her visit, and noted the international spotlight that Canada has been under in 2010, with the Olympics, the G20 and G8 meetings, and its strong economic position.

He went on to pay tribute to the country's "noble heritage," fashioned at first by aboriginal peoples, the French pioneers, and the British adventurers and loyalists.

"And, of course, the faith of every immigrant man and woman, from every corner of the globe, who, with the world to choose from, has declared, `I will be a Canadian.' They have made us all the true north, strong and free."

Following the show, and the flypast of nine Snowbirds, the royal couple met with the performers and walked past the rows of dignitaries who sat immediately in front of the stage. Among them, Canadian astronaut Chris Hadfield, who said the Queen seemed taken aback to hear what he did for a living.

"She asked where I had been in space, and what I had done, and what the experience was like, and for me she's just a great example of what civilization and humanity should aspire to," said Hadfield "I have tremendous respect for the Queen and the monarchy and what they do for Canada, and it was a tremendous privilege to meet her."

Moose Jaw, Sask.-based Canadian Forces Snowbird Capt. Eric Willrich gushed about meeting the Queen during her brief walkabout.

"Being in her presence was just super cool. My mom is just her biggest, super fan and she's probably at the house dancing right now. It's amazing, a once-in-a-lifetime opportunity to say hi to the Queen."

The Queen left Parliament Hill without meeting with any of the public gathered behind the barricades, but smiled broadly as she left to get into her awaiting black limousine.

Across the country, Canadians whooped it up for the nation's birthday.

Hundreds of people clad in red and white gathered at Citadel Hill, the historic fort in Halifax, to celebrate Canada Day.

The sidewalks below were packed earlier as a parade by the Royal Nova Scotia International Tattoo wound through downtown Halifax.

Among the crowd was Clarence Hewitt, who said the celebrations were a nice way to top off a week of festivities in Halifax, which included the Queen's visit and an international naval fleet review.

Justine Scilipoti, a student at Dalhousie University originally from Ontario, was celebrating her first Canada Day in Halifax. She said it's important to celebrate the fact that Canadians live "in the best country in the world."