Thousands of cyclists began the long ride from Toronto to Niagara Falls on Saturday to raise money for cancer research.

The 11th annual event, The Enbridge Ride to Conquer Cancer, drew a total of 4,555 cyclists and raised $18.3 million for the Princess Margaret Cancer Centre in Toronto. The cyclists are expected to finish in Niagara Falls on Sunday after pedalling more than 200 kilometres.

​"We're all here this morning because cancer has touched our lives in some way," Dave Charleson, vice president of energy supply and customer care for Enbridge Gas Distribution, told a crowd of riders at Exhibition Place.

"We're here to celebrate survival. We're here to honour loved ones lost and to give hope to loved ones who continue to fight."

We are grateful to all of those who participated in <a href="https://twitter.com/TheOntarioRide?ref_src=twsrc%5Etfw">@TheOntarioRide</a> this year. $18.3M raised. Thank you for your support!! 🚴🏾‍♂️<a href="https://twitter.com/hashtag/TheRideTO?src=hash&ref_src=twsrc%5Etfw">#TheRideTO</a> <a href="https://t.co/YOeuy7N9U1">pic.twitter.com/YOeuy7N9U1</a> —@thePMCF He said it was a "tremendous sight" to see so many riders in one place.

During opening ceremonies in Toronto, a riderless bike was escorted through the crowd to symbolize those who lost their lives to the disease.

Michael Burns, president and CEO of the Princess Margaret Cancer Foundation, said in a news release that the event brings together cancer survivors, cyclists and supporters who train and raise funds all year.

"With this being my first year riding, I am truly amazed by the community of participants and supporters who dedicate their year to this incredible event," Burns said.

Over the last 11 years, the ride in Ontario has raised more than $194 million for "personalized cancer medicine" at Princess Margaret Cancer Centre. Nationwide, rides have generated some $396 million to date.

Almost 1 in 2 Canadians develop cancer

An estimated 565 Canadians are diagnosed with cancer every day and nearly 1 in 2 Canadians will develop cancer in their lifetimes, he added.

A plane flew over the crowd with a banner celebrating the fundraising efforts of the Ride to Conquer Cancer in Ontario. (The Ontario Ride/Twitter)

For Abby Micks, a first year rider from Toronto, June 9th marks the start of a six-year cancer journey.

"I was diagnosed with melanoma on June 9, the exact date of The Ride this year, and every June, I do something special that pushes my physical limits," Micks said in the release.

"Despite my personal battle, I am also riding for family members who have been affected by the disease. In the last few weeks, my closest cousin, who was like a brother, lost his battle."

The Princess Margaret Cancer Centre said the money will help it to detect, diagnose, support and treat more than 17,700 new patients every year.

On Saturday night, the CN Tower and Toronto sign in Nathan Phillips Square will be lit blue, yellow and white in support of the ride.

Similar rides are scheduled throughout the summer in Quebec, Alberta, and B.C.