Trivia: An estimated 800 children from a local school were used as extras for the scene in which Rocky runs through Philadelphia.
Trivia: The smaller quicker fighter that Rocky is sparring with before the fight is real life champion Roberto Duran.
Trivia: During the run when Rocky runs up the steps, when the kids run around the roundabout the kid in the second row trips and knocks a load of other kids.
Trivia: Boxer Chuck Wepner, the partial inspiration for Rocky, was going to have a small part in the film in the boxing gym but he declined cause his audition went too wrong. By his own admission he went on a drink and drug booze binge before driving overnight to the audition. He later said "I should have taken more time, should have studied the script. Stallone did everything he was supposed do, and if I would have done better, maybe I would have gotten the part."