PITTSBURGH - More than 300,000 black-and-gold bedecked Pittsburgh Steelers fans — about the population of the city itself — packed the streets of “Sixburgh” on Tuesday for a parade celebrating the storied franchise’s unprecedented sixth Super Bowl title.

From infants to senior citizens, fans braved freezing temperatures and crowds so deep that for some even seeing the parade was impossible.

Not that it mattered. Many just wanted to be part of the festive atmosphere and have the chance to revel in the team’s 27-23 victory over the Arizona Cardinals in Sunday’s Super Bowl. Rousing chants of “Here we go Steelers!” pulsed through the crowd as they waited for the team to make its way along the route.

“We’re going to tell the school we had fever — Steeler fever,” 12-year-old Rachel Russell said, excusing her absence from school before leading a Steelers chant.

Renaming the city Sixburgh for the day, Pittsburgh Mayor Luke Ravenstahl made his way through the parade alongside quarterback Ben Roethlisberger, both filming the crowd that painted a gray sky yellow with twirling Terrible Towels.

Fans filled parking garages, skyscraper windows, balconies and even climbed trees to get the best view of the team they love and possibly find shelter from the sporadic flurries and temperatures that hovered in the mid-20s.

“It’s never too cold to watch the Steelers,” said Annette Mowery, 47, who drove from the Pittsburgh suburb of Mars with her children, Lexie, 12 and Lucas, 10.

“We didn’t have a good day, we had a great day. It’s history,” Lucas said, a Super Bowl XLIII hat perched atop a blue ski mask, a matching T-shirt squeezed over his jacket.

Even police got into the spirit, waving Terrible Towels from atop horses as they led the parade. Coach Mike Tomlin followed behind in the back of a red convertible, while players holding video cameras cheered and waved from the back of pickup trucks.

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Tomlin couldn’t stop smiling as he was greeted on stage at the end of the parade route with thunderous applause.

“What do you say to this?” Tomlin asked the massive crowd. “Steeler Nation, you leave us all speechless, man, we just appreciate the love. How about the Steelers? How about the greatest fans in the world? How about number six? Thank you, we love you guys.”

Steelers owner Dan Rooney thanked the city for its support over the years — and said there is more history to be made.

“Stay with us,” Rooney said. “Maybe we’ll get the seventh next year.”

One by one, coaches and players spoke to the crowd. Wide receiver Hines Ward, MVP of Super Bowl XL, led the fans in a chant of “Here we go Steelers, here we go,” while other players danced and did an impromptu rap.

Steelers linebacker James Harrison, whose 100-yard interception return for a touchdown was the longest in Super Bowl history, presented the Lombardi trophy to the crowd. About the same time, huge booms of colorful fireworks exploded over downtown’s Point State Park, at the confluence of the iconic three rivers.

Police spokeswoman Diane Richard estimated more than 300,000 people attended the parade — more than the 250,000 fans who attended the 2006 parade celebrating the team’s previous Super Bowl victory and close to the city’s population of 311,000.