Sylvester Stallone's 72-step climb to stardom was celebrated Sunday to mark Philadelphia's inaugural "Rocky Day."

Nearly 50 years after "Rocky" was released, the City of Brotherly Love welcomed the star and screenwriter back to commemorate the boxing film's impact.

Stallone, 77, likened his early struggle as an actor and writer to his character Rocky Balboa's climb to success. "Naivete is great. You have all of these dreams and aspirations, and you haven’t been embittered yet when life beats ya down. I was very ambitious because there was no 'plan B.' At the time, all I had to fall back on was my butt," he told the crowd outside the Philadelphia Museum of Art, according to The Philadelphia Inquirer.

"'Rocky' was just a perfect storm. It came along at a time when politics were changing and people were looking for more positivity, and I just happened to fall into it," the Oscar-nominated actor added.

Stallone referenced the difficult climb to the art museum, an iconic moment in the "Rocky" movie, where the boxer sprints up the steps to the song "Gonna Fly Now" as part of a grueling workout.

"To me, when you get up there, you feel like you can be the champion of your dreams," he told Sunday's audience.

"But the real victory is never giving up and going the distance for yourself and your loved ones. Standing at the top, you are reminded that all things are possible," he said, in a video shared by 6ABC. "Keep punching!"

Stallone told 6ABC the time since the film's release "has gone by in a blink."

Every 'Rocky' movie,definitively ranked (including the new 'Creed III')

"I haven't done enough in Philadelphia, I really haven't. I want to do more," he declared. "This 'Rocky Day' has kicked it all off and it's going to be a good time. I am going to give back to this city that has given me so much."

The first official "Rocky Day" was also marked with the opening of the Rocky Shop inside the Philadelphia Museum of Art, which houses the film franchise's only official merchandise.

"Rocky" became a franchise with five follow-up films through 2006 and birthed the Michael B. Jorden-led "Creed" spinoff, which has three movies.

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