17,000 runners from around the city, and the world, took place in the event.
It all started along the Ben Franklin Parkway around 7 a.m. where runners got going, and after a scenic route throughout the city, culminated near the Art Museum.
Katie Florio of Center City was the top female runner. She just had a baby a year ago.
"Living in the city, I run these streets every day; it was cool I knew the tangents, I knew the course," Florio says.
Athletes crossed the finish line after their 26.2 mile trek. Spectators lined the route as these marathoners took in the city, all ending back near the art museum.
"it is an easy city to navigate. It's based on a grid system, so you are able to see loved ones at the start, then you can see them at the halfway mark and then make your way to see them around mile 14 and the finish line," says Race Director Kathleen Titus.
Many athletes run for a cause, saying it propels them. American Association for Cancer Research is the title sponsor.
"You hear people talk about that they're out on the course and they're alone with their thoughts but also alone with their loved ones who might be going through a cancer diagnosis," says Sam Rogers of AACR.
"I'm raising money for veteran and first responder mental health," says Brian Reed of Hudson Valley, New York.
"It's my 40th birthday weekend so I signed up to run with my dad and sister and just give back to my hometown," says Erica Mitchell, who traveled her from Minneapolis to take part in the race.
The top male runner was Will Loevner from Pittsburgh. He still can't believe it, as he only recently got into marathoning.
"It's like a dream come true, when I got into marathoning last year, it would be hard to believe I could pull this off," says Loevner. "This year I wanted to come back to Philly and try to win."
Loevner says he is expecting a baby in the next few months and he's thinking about using the prize money on a jogging stroller.