Four days before 13-year-old Long Island native Gianna Pizzulli visited Philadelphia with her parents, she watched Rocky for the first time — somewhat reluctantly — at the suggestion of her mom, Cindy.

"Is it in black and white?" Gianna asked her parents. "It's so old!"

But the teenager ended up loving the film and added a stop at the Rocky statue near the Philadelphia Museum of Art to her family's vacation agenda. They decided to check it out during a hop-on, hop-off bus tour Friday morning.

But what was supposed to be a low-key bus tour took a surprising turn when the Pizzulli family arrived at the statue.

Sylvester Stallone himself was standing in front of the Rocky statue.

Dozens of cheering fans surrounded the actor, who is in town filming Creed II, the sequel to Ryan Coogler's Rocky series spinoff. Tour buses that were rounding the corner slowed as visitors whipped out their smartphones in disbelief.

Stallone met Mayor Kenney at the foot of the statue to rededicate its plaque. He tapped the statue a few times before turning around and doing the Rocky pose — his fists raised, imitating the look immortalized in bronze — much to the delight of onlookers, who began chanting, "Rocky! Rocky! Rocky!"

Kenney also presented Stallone with a personalized Eagles jersey. Afterward, the actor posed for photos with the throngs of fans, which grew by the minute.

The statue is one of two commissioned by Stallone before the release of Rocky III in 1982. Sculpted by A. Thomas Schomberg, the statue was originally installed at the top of the famous steps before eventually moving to its current location at the bottom. The statue's placement has not been without controversy, as it sparked a debate about whether it was "art" or just a "movie prop." Last December, Stallone purchased the backup statue for $400,000.

Stallone's last formal appearance at the famous steps was in 2015, when Creed was released. At 69, he won his first Golden Globe as best supporting actor for his performance in Creed.

Stallone said it felt fantastic to be back in Philly. He also said that the city had drastically improved since he had filmed Rocky here over 40 years ago.

"It's like I never left here," he said. "I am Philly, Philly is me. My life began here, you know?"

As for Creed II, Stallone said that the movie will be just as good as the first one.

"Buckle your seat belts," he said. "Because Michael B. Jordan is coming."

After Stallone left, fans were still shocked. Two visitors who had showed up a little too late to catch the actor were in complete disbelief when they found out he had been around, until Pizzulli whipped out her phone to show them photos and videos.

"When I saw him from the top of the bus as it turned around, I thought, 'There's no way!'" she said. "We immediately got off the bus so we could get a better look, and it really was him."