Big Boy (locomotive)

Big Boy was a massive steam locomotive built by Union Pacific in the 1940s, designed for hauling heavy freight across challenging terrains like mountains. It features a 4-8-8-4 wheel configuration, meaning it has four leading wheels, two sets of eight driving wheels, and four trailing wheels, providing stability and power. Known for its size and strength, Big Boy could generate immense tractive effort, making it one of the largest and most powerful steam engines ever constructed. It symbolized engineering ingenuity during the steam era and played a key role in freight transportation in the western United States.