The runners – many dressed in bright pink outfits – set off on routes around York Racecourse.
They did this to raise money for Cancer Research UK and support her life-saving work.
In the morning, participants took part in 10 km and 5 km races on the running track.
This afternoon, both children and adults will take on a Pretty Muddy obstacle course where they will climb, crawl and slide around a 5km course on the Knavesmire.
Event manager Amy Seymour said a total of 3,000 attendees are expected across all events.
“It’s going to be a great day,” she told The Press ahead of time. “It’s super important that these events are happening in the fight against cancer.”
The runners included people new to the sport, experienced participants and also children.
Brian Hall ran his first 10k race at the age of 91.
“I feel good,” he said an hour before departure. “I’ve never raced before. It’s a one-off, I have to stay fit.”
The great-grandfather, dubbed “the magic man” by friends, previously told The Press he decided to take part in the Race for Life after being urged to do so by his trainer Denise Cooper.
On race day, Brian, originally from Leeds and now from York, wore a pink tutu and wig. He said this got him an extra £10 from a woman he met in a pub beforehand.
He added that he has raised £500 for Cancer Research UK so far.
As for what he would do after the race, Brian said: “I’m going to get some food afterwards to celebrate.”
Elizabeth Jones participated in the Race for Life for the seventh time.
But for Elizabeth, it’s not a race, but a chance to raise money in the fight against cancer.
She walked in memory of her daughter-in-law Monica Braginton, who died of breast cancer three months after her marriage to Elizabeth’s son Neil.
Elizabeth raised £300 for her participation.
Five minutes before starting the 10K route, she said, “I’m going to get it done.”
‘It takes me out of my comfort zone’
Runners were cheered as they made their way around the course before crossing the finish line for the final time.
“I feel good,” Rachel Hyde-Smart said after crossing the line. “I do a lot of fitness but not a lot of running.”
Despite this, she completed the 10 km run in 55 minutes.
“It takes me out of my comfort zone,” added Rachel, who lives near Selby. “Cancer is such a terrible thing, so it’s good to put myself in that position and raise money for a good cause.”
Monika Schmid completed the 10km run with her colleagues from the Faculty of Language and Linguistics at the University of York.
“It was great,” she said. “I’m glad it’s not as hot as it was earlier this week.
“It is a very nice course with a lot of encouragement along the way.”
The team raised approximately €1,000 for charity.
On why she took part, Monika explained: “Like everyone in the world, I know people who have had cancer.
“My husband Chris was treated for leukemia eight years ago.”
Her teammate Ellie Rye said her mother Sue had lost her battle with cancer so she took part.