Updated July 11, 2026 at 8:14 AM MST
Union Pacific Railroad's Big Boy No. 4014– the world's largest operating steam locomotive – has been barnstorming from coast-to-coast in a celebration of America's 250th birthday. Based in Wyoming, the train came east to Philadelphia for the July 4th weekend.
On the hottest day of the year – 102 degrees with a heat index that made it feel like 112 – dozens of people camped out by the side of the tracks at Valley Forge National Historical Park to see the train steam by. Many people brought camp chairs and coolers with water, like John Seibert, who came with a couple of friends from a model railroad club.
"It's a once-in-a lifetime experience," he said, "I mean you're never gonna see it again."
Many in the crowd checked their smartphones to see the progress of the train on an app, as it made its way down the track. And from miles away, you could hear the whistle. Then, the crowd could see the headlights in the distance. Then the Big Boy, 133 feet long and weighing 1.2 million pounds, came barreling past, bells ringing and steam whistle blaring.
"It was pretty amazing," exclaimed Seibert. "When he blew the whistle right by us, it kind of went right through you."
A few days later, engine 4014, and the 18-car long Union Pacific train it pulled, parked in Philadelphia's Navy Yard, where crowds could get up close and personal. Fifteen-year-old Brandon Westerfield of Leonardo, New Jersey, came with his mother.
"I mean it's obvious, but it's huge," said the young train enthusiast. "It's so cool to see just something that big right in front of you."
His mother, Althea, who has seen many trains with her son, said: "When he told me about it, I was like, okay, it's another train, but now that I'm here, this is absolutely incredible. I've never seen such a sight."
A train and its celebrity
The Union Pacific Railroad Company ordered twenty-five Big Boy locomotives, from 1941 to 1944, to haul freight through the Wasatch Mountains in Utah and Wyoming. The engines had an articulated design, to allow them to take curves, and two sets of pistons, driving eight wheels each. The last Big Boy retired in 1962 - they were all replaced by diesel engines.
Eight of these behemoths were preserved, but only one – number 4014 – is in operating condition. The restoration of the engine was overseen by Ed Dickens, senior manager of Union Pacific's Heritage Operations. He's also the train's engineer.
Dickens is straight out of central casting, with his overalls and cap with the Big Boy's number on it. He's usually the guy at the throttle of this 7000-horsepower beast, as it hauls the train across the country.
"It's all manually operated, there's nothing automatic," Dickens explained, after a round of selfies with fans of the Big Boy.
"Ed Dickens is just a super ambassador," said Matt Zollers, who came from Hatsboro, PA, to see the Big Boy. "What a great guy, great representative of the Union Pacific. Takes his time to talk to everyone, so friendly, so shout out to him."
"From a personal standpoint, seeing the happiness, seeing the crowds is something that's just spectacular for us," Dickens said, standing in front of the engine.
Over two days, close to 100,000 people visited the Big Boy in Philadelphia. But all too soon, it departed on its way back home to Wyoming. It'll have stops in Pennsylvania, Ohio, Illinois, Missouri, Kansas and Colorado along the way.
Dickens had a word about safety for folks who want to catch it, as it passes by their towns: "Please don't hesitate to tell your fellow Americans, 'Hey people, I talked to the train engineer and he told me to tell you to stand back. Always 25 feet back.'"
And, if not, the Big Boy's whistle will most certainly warn them.
Copyright 2026 NPR
