By the time Rachel Le Vance met Jason Phillips four years ago, she already knew that her body had turned viciously against her.

The couple were only in their 20s and Rachel was upfront about the aggressive cervical cancer that would ravage her reproductive organs. But Jason had already fallen hard for the woman who would become his fiancée. Over the next three years, Rachel would endure a radical hysterectomy, chemotherapy and a desperate fight for her life against a ruthless, relentless cancer with Jason by her side.

"We defied cancer by living every day as if there were no tomorrow, because there wasn't," Phillips said during a roadside lunch break along the final stretch of the Philadelphia 2005 Susan G. Komen Foundation Breast Cancer 3-Day Sunday.

The event is a grueling "walk for the cure" that takes place in a dozen cities every year. Participants walk 60 miles in three days, camping in tents overnight.

Although Rachel did not have breast cancer, she decided she wanted to participate in the 3-Day in the couple's hometown of San Diego in 2003. She convinced Phillips to join her. By the time of the event, Rachel's condition had deteriorated.

"She was two weeks into the chemo and she walked without a blister, without complaining," Phillips said.

The pair planned to walk again last year in the San Diego event when Rachel underwent emergency surgery. Phillips wanted to push Rachel the distance in a wheelchair, but an inoperable, fist-size tumor had invaded the space in Rachel's body where her cervix once was.

As Jason and Rachel's best friend maintained a bedside vigil, Rachel, unable to speak, indicated through hand motions that she wanted to write. She sketched the word "walk" on a pad and struggled to make facial expressions to convey her meaning.

"It was like something from a movie, she wanted us to walk," Jason said.

They did. A few days later, Rachel LeVance lost the fight of her life. She was 32.

"I watched her youth taken away," Phillips said of woman he described as "my life, my sweetheart." "By the end, she had the body of an 80-year old, but the spirit of a prizefighter," he said.

Phillips, a fit, athletic-looking 30-year-old with a shaved head, wore a T-shirt with Rachel's picture on the back and a "F*** Cancer" slogan scrawled across the front. A pink baseball cap bears the same slogan. His sister Elizabeth, walking with him, is similarly attired.

They will rest up from the Philadelphia 3-Day, and in three weeks, on the first anniversary of Rachel's death, will walk 60 more miles with a team in their hometown of San Diego.

The Phillipses were among more than 2000 walkers who converged in Philadelphia over the weekend for the 3-Day, a monster of an event that attracted walkers from 40 states, as well as Germany and Puerto Rico. The walk raised $6 million for breast cancer research, awareness and screening.

The walkers came in all shapes and sizes — young and old, male and female, fit and not-so-fit. As they walked, then trudged, then eventually hobbled through the breathtaking--if much too hilly landscape of Bucks and Montgomery Counties, Pa.--the common thread among them was that someone they cared about had either been diagnosed with, or lost to, cancer — overwhelmingly, breast cancer.

"It's a very humbling experience," said Kay Borne, a walker from Erie, Pa. "You think, 'I'm walking; someone else has cancer.'"

Like most of the walkers, Borne was not alone. Her four-person team, Simply Irresistible, got involved with the 3-Day last year when they learned that a woman from Borne's aerobics class, Mary Brumbah, was fighting breast cancer. Brumbah lost that battle.

"Last year we walked in honor of her. This year, we walked in memory of her," said Born, unfurling a pink banner covered with the names of the breast cancer survivors and victims in whose names donations to her team were made.

Born wore the banner like a scarf.

"We tell [donors] we'll take them with us the whole 60 miles," she said.

According to the Komen Foundation, 211,240 new cases of breast cancer are expected to occur among American women in 2005 — an estimated 40,410 will die from the disease. It is the most common cancer among women of all ages, the most proven risk factors to date being female and being older. Deaths from breast cancer have dropped every decade since 1990, however, and the 5-year survival rate for women with localized breast cancer is more than 95 percent. There are currently more than 2 million breast cancer survivors in the U.S.

There is nothing easy about walking 60 miles. Depending on one's level of fitness, training for such an event can take the better part of a year. Before the walkers could take one step, they were required to raise a minimum of $2,100 in donations. For many, the 3-Day is the culmination of a yearlong commitment to training and fundraising.

By all accounts, however, the first day was brutal. Starting out at Sesame Place in Langorne, Pa., walkers logged more than 24 miles under blistering heat. Late on the second day, the toll was obvious. Knees were wrapped in bandages, blistered heels and toes were taped up and muscles were stiff or swollen. Many limped, others removed their sneakers and planned to finish up in flip-flops or sports sandals to make room for their bandaged toes.

During the first day, the medical staff administered 100 IVs and 10 people were hospitalized. The second day was much better: No hospitalizations and just 10 people needing IVs.

But despite the physical toll, the walkers' determination was as fresh as ever. With photographs of lost loved ones taped to their backs, many walkers said that whatever discomfort they felt, it's better than walking one step in the shoes of a cancer survivor.

Eat, Drink and Be Merry

While many of the personal stories are devastating, the mood during the three days is nothing if not festive. At the pit stops every three miles along the route, upbeat music blasts from speakers while walkers congregate on the grass and an impossibly cheery and helpful crew and medical personnel attend to their every need. Snacks, fruit, sandwiches and drinks are in plentiful supply beneath giant tents, a "gang" of female bikers has volunteered to do traffic control and crowds cheer on the walkers at every turn.

Once the walkers reach camp for the night, there are hot showers, hot meals, neat rows of pup tents for bunking and entertainment: karaoke Friday night, a band and dancing Saturday night.

But nothing captured the carnival spirit like the outfits: Elaborate homemade hats festooned with ribbons and feathers, Roman crowns of fake flowers, strings of beads and pins, bright bandanas flapping in the breeze, hair dyed unnatural shades of pink, giant, colorful wigs, clown suits, wings, head bands with fuzzy antennae, T-shirts covered in names.

Most of the teams wore matching outfits, like Buddies for Breasts, a 50-person team whose members wear baseball caps with Styrofoam breasts affixed to the front. The hats are the creation of team organizer Janet Van Pelt of Annapolis, Md., who recruited her team online through the 3-Day website and message boards and met many of them for the first time when they arrived in Philadelphia for the race.

"When I finally met them, it was like meeting old friends," said Van Pelt who named the team for her friend Jamie Calehuff, who died from breast cancer. "She called everyone 'buddy,'" Van Pelt explained.

Van Pelt walked with a 14-person team in the Washington, D.C., event last year. She spent the past year running training walks and pulling her 50-person squad together. They were the first place fundraisers, collecting $126,000.

While Van Pelt's "boobhead" hats garner lots of attention, the queen of this ball — were there to be one — would likely have been Pamela Kerr, a San Diego physical education teacher. Kerr was decked out in a pink lace tutu, a pink cowboy hat with lace strips that tied beneath her chin, shiny pink pom-poms fastened on the front of her sneakers and several bras — a 44 D-cup decorated with buttons and jewels strapped around her hips and a training bra forming the band around her hat.

This was Kerr's third year walking the 3-Day. To honor that achievement, Kerr plans to walk in three 3-Days — 180 miles. She participated in the Boston event a few weeks ago and will walk with her team, the Princess Blister Sisters, in San Diego in three weeks.

Her 32-person team includes four breast cancer survivors. They have raised $64,000 and are shooting for a goal of $75,000. Kerr's grandmother died of breast cancer when she was 10-years old, but Kerr said she walks to promote her personal philosophy about fitness.

"There's a dimension of fitness that involves the heart," Kerr said, speaking not of the muscle that pumps blood but the spirit that is nourished by doing good works. "You have to give back, that's what I'm trying to teach the kids. This is a way of giving back and getting fit," she said.

Check back here tomorrow for Part 2 of Robin Wallace's coverage of the Philadelphia Breast Cancer 3-Day.

October is Breast Cancer Awareness Month. Since October of 2004, FOXNews.com has published more than 65 stories on breast cancer. To read these stories, click on the Related Stories box above.