The Duke and Duchess of Cambridge celebrated Canada Day with fireworks on their first official international outing.
Jubilant Canadians thronged to catch a glimpse of Prince William and his wife Kate, who joined nearly one-third of the capital city's population of 900,000 who cheered "Will and Kate" on the Parliament lawn.
"We love you Kate," one section screamed when she stepped out of the carriage.
The crowd, decked out in red and white, Canada's national colours, ballooned to 500,000 by nightfall when fireworks lit the sky.
Kate, wearing a purple Issa jersey dress, and William, who had by then thrown off his necktie, were dazzled with pyrotechnics on Parliament Hill, framed by some of the finest Gothic Revival architecture in the British Empire.
"Catherine and I are thrilled and excited by the prospect of the next eight days," William said. "It will be an adventure that we will never forget."
Thousands had lined Ottawa's Wellington St at dawn to secure a view of the royal couple when they made their way to the city's government precinct.
Far more Canada Day revellers showed up than usual, indeed "a record" and maybe triple the number that came last year for the Queen's visit, said Prime Minister Stephen Harper. "The excitement is palpable here," he said.
Under a blistering sun, a few fans collapsed and were carried off by medics. Those who coped were treated to a fly-past of fighter jets, a changing of the military guard decked in red tunics and towering bear fur hats, as well as Canada's national anthem sung by a 10-year-old girl from Winnipeg.
William said his new bride learned about Canada from her grandfather, who died last year, "but who held this country dear to his heart, for he trained in Alberta as a young pilot during World War II".
The prince also conveyed his grandmother's "warmest good wishes".
Queen Elizabeth II, he said, has taken a "great interest" in the couple's trip to Canada and will be "following our progress as it unfolds".
Packed with pomp and pageantry, the North American tour marks the couple's first foreign trip as newlyweds.
Over the coming week, William and Kate are to take a cooking class in Montreal, play aboriginal sports in the far north and cap it off with a rodeo in Calgary.
Their tour of Canada, however, also coincides with a grim milestone: Friday would have been the 50th birthday of Princess Diana, Prince William's mother, who was mobbed by fans when she visited Canada in 1983.
Prince Charles often seemed annoyed at being upstaged by his wife but William appeared to rejoice at the Canadian public's attention to his new bride.
He visibly brimmed with pride as they shared a few glances whenever enthusiastic cheers erupted for her, and once blushed over their wild welcome.