(CNN)– The world’s largest steam train is heading East to help celebrate America’s 250th birthday. Union Pacific’s Big Boy number 4014 begins the Eastern leg of its trip in late May. The historic train will visit 10 states. Events are planned in 8 cities, including a Fourth of July celebr ation in Philadelphia. This will be the first time Big Boy has crossed the Mississippi River and into the Ohio Valley since it was built in New York and delivered to Union Pacific Railroad in 1941. Categories: News ...read more read less