Train enthusiasts around the region are eagerly anticipating a rare opportunity.
On June 10 and 11, Big Boy No. 4014, the world's largest operating steam locomotive, is scheduled to roll through western New York as part of its coast-to-coast tour in celebration of the country's 250th birthday.
"It is a visceral experience, you can hear it coming, you can feel it coming, it's 1.2 million tons, it's 133 feet long, that's almost half the size of a Boeing 747," said Robynn Tysver, a spokesperson for Union Pacific Railroad.
This will be a kind of homecoming for the train. Big Boy typically travels through the western part of the country and hasn't returned to New York since it was built in Schenectady in 1941.
On its national tour, it's been drawing huge crowds of rail enthusiasts. Tysver said more than 70,000 people showed up during a two day display day in Ogden, Utah. Jeremy Tuke is a local train fan who said he can't wait to see it.
"They're really an engineering marvel, and to be able to see one operate close by is really a kind of a once-in-a-lifetime experience nowadays," he said.
Big Boy's scheduled stop in the Buffalo area will be near the Walden Galleria shopping mall from 9 a.m. to 2:30 p.m. June 10. There will be a shuttle service at the mall.
Then, on June 11, the train is expected to pass over Letchworth State Park's scenic Genesee River Arch Bridge around 12:20 p.m.
Tuke said he's assuming that traffic around the train's route will be a nightmare, so he has a plan to work around that by finding a more remote crossing area near the park.
"My interest really isn't in taking pictures of it, so much as I would like to be trackside in a couple of places just to experience it passing by the sights, the sounds, the smells," he said.
Luckily, you don't have to get too close to experience Big Boy's deep whistle echo across the landscape. Tysver said you should be able to hear it from a mile and a half away.