For three days, some 3,100 people will walk 20 miles per day. It's the "Breast Cancer Three Day," a walk for hope and an inspiration for all the women who have been lost to the disease, and for all the woman who have survived it.
By Sunday they will have walked 60 miles around the Philadelphia area.
Participants said it was worth the exhaustion.
"The last two miles were very hard, but I just kept whispering the names of the women I'm walking for," said Michelle Mack of West Mount Airy.
One of those women is Lee Johnson, a two time survivor of the disease.
"You learn people's stories and you learn that you find they have worse stories than yours but you go on," Johnson said.
Many of those stories can be found in the remembrance tent. It's lined with pictures of women who once walked themselves.
"Just seeing everyone and the loved ones they lost and the loved ones I lost," said Ashley Hoffman of Jenkintown, PA. "The one picture really upset me because there's a woman who died and she two small children. It's very hard to see that."
On group stood outside their pink tents and shared memories about their friend Elise Gambos. She was described as a vibrant young woman who survived Hodgkin's as a teenager and breast cancer at just 23.
For the last two years she was a top fundraiser for the 3 day. But just months before this year's walk, she passed away from a blood infection.
Her boyfriend and 40 of her friends and colleagues walked in her honor, raising about $85,000 so that one day these men and women won't have to walk anymore.
"She was a very brave person, and you never hear about it. The way she lived her life, took on the world. She was an inspiration to everyone," said Terry Feather of Wayne, PA.
"It's just amazing. I know she's here with us helping us make it through," said Jennifer Degaetano of Mechanicsburg, PA.
Fundraising for the three day walk is expected to exceed $6.3 million right here in Philadelphia.