In Vancouver more than 48,000 runners turned out for the Vancouver Sun Run, according to organizers.
The Sun Run, Canada's largest road race, was one of many previously scheduled and hastily organized running events Sunday that paid tribute to the Boston victims.
Steve Bermann, 49, made sure he wore blue and yellow, the official colours of the Boston Marathon, in his first time running in the event.
"I heard that we were commemorating victims of the Boston Marathon, so I thought it was really important to support the people in Boston," said Bermann, a North Vancouver man who works as a high school guidance counsellor.
In Montreal, several hundred people met at the foot of Mount Royal to run up the mountain together.
Odette Beaudry, a runner in Montreal who competed in Boston this year, felt very lucky to avoid the bomb blast, which went off after she had already finished the race.
"It's really in solidarity," Beaudry, 47, said of her decision to run on Sunday.
"The marathon is a totally apolitical, peaceful event that brings people together."
A similar run was held in Quebec City.
Back in Vancouver, Sun Run chief organizer Jamie Pitblado was glad to have "great weather, a great event and a great crowd."
"It showed that running can unite," he said.
Before the race, a moment of silence was held for the three Boston bombing victims who died, including an eight-year-old boy, and more than 180 others who were injured when two separate bombs went off near the finish line of the Boston Marathon.
Christopher Imai was one of this year's Boston marathoners who ran in the Sun Run. Imai had crossed the finish line in Boston and left the area before the bombings occurred.
"I just wanted to be part of Vancouver and I also know Vancouver people are feeling for this tragedy," he said.
B.C. Premier Christy Clark showed her spirit by taking part in the run while in the midst of a busy election campaign against NDP leader Adrian Dix, who was trying to woo support for his party elsewhere.
Clark, who signed up for the Sun Run weeks in advance, sported a Boston Red Sox hat while her supporters wore yellow Team Clark T-shirts.
Paul Kimugul of Kenya won the race in 29:04 after being saddened on Monday because friends had run in Boston. Ian Burrell, 28, of Tucson, who finished second overall just a split second back, called the Sun Run "really uplifting." He said the boisterous crowd contradicted the sombre atmosphere that he was expecting.
"It was really amazing to see everyone coming out here and, essentially, saying that we're not going to let those events deter us from enjoying our lives and getting on with it," said Burrell.
— With files from Keven Drews in Vancouver and Ben Shingler in Montreal.
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