As Canada Day celebrations kicked off on Parliament Hill on Monday, most thoughts were with those in southern Alberta, still cleaning up after last month’s floods.

In his annual Canada Day speech on Monday, Prime Minister Stephen Harper told crowds that the generosity, perseverance and tenacious spirit of Albertans set an example for the rest of the country.

"When floods forced so many from their homes, communities dug deep, neighbours helped neighbours and people sheltered complete strangers," Harper said during his annual address from the foot of the Peace Tower.

“That’s the spirit that makes Canada the best country in the world – bar none.”

In a video message, Alberta Premier Alison Redford also thanked Canadians for coming to the aid of her province’s flood victims.

“Thank you so much from the bottom of our hearts,” Redford said in the video. "On this Canada Day we are so grateful to be part of a Canadian community.”

Under overcast skies, thousands of spectators assembled in front of a large stage and watched as dignitaries including Harper and Gov.-Gen. David Johnston arrived with their families.

As the ceremony got underway, Johnston inspected the guard of honour and received the vice-regal salute.

On stage, opera singer Measha Brueggergosman sang “God Save the Queen.” Jennifer Gillis followed to lead the crowd in “Oh Canada.”

Harper welcomed Canadian astronaut Chris Hadfield to the festivities. Hadfield, who gained international fame during his stint on the International Space Station earlier this year, is performing at the show.

Harper ended his remarks with a quote from Stompin Tom Connors, who passed away earlier this year: “Be the Patriot Canada needs.”

Addressing the crowd, Johnston also paid tribute to the Alberta flood victims and military personnel.

He said the holiday is an occasion to celebrate Canadians who embody the ideals of valour, service and excellency, including those heroes who “live in the shadows.”

“I challenge you this year to do and give what you can to make our country smarter and more caring, fairer and more just, stronger and more united,” he said to the crowd.

Like Harper, Johnston acknowledged the passing of Stompin Tom Connors, putting a twist on a line from “The Hockey Song.”

“Hello out there, we’re on the air, it’s Canada Day today,” Johnston sang.

In a taped video released earlier Monday, Johnston noted that Canada’s 150th birthday is just four years away.

“With that milestone in mind, let us each strive to discover what we have to give to this country. The essence of democracy is understanding that we all have something to give, and a responsibility to do so.”

Celebrations across the country are marking Canada Day with fireworks, musical performances and celebrity appearances.

In addition to a musical appearance from Hadfield, the Parliament Hill show featured a performance by pop singer Carly Rae Jepsen.

Speaking with CTV’s Don Martin on Parliament Hill, Heritage Minister James Moore said as a world leader in arts, culture and science, Canada has a lot to celebrate.

“You see things like the flooding in Calgary where you see the best of Canada stepping up to help your neighour when nobody asks you to, but you know it’s the right thing to do,” he said.