Many of the participants taking on the 228-kilometre long trek are cancer survivors and those who've lost loved ones to the disease.
Canadian Olympic gold medallist Alexandre Bilodeau traded his skis for a bike and said he's taking part because cancer touches just about everyone.

“It’s been in my family and it's been everywhere, it's something that we will be very supportive of. A lot of people here today are survivors of cancer. It's something very impressive that they achieved and they conquer. Altogether we're heading in the right direction and we're one step closer to finding a cure,” he said.

Participants in this year's event have raised more than $4.9 million so far.