The Baltimore & Ohio (B&O) Railroad played a big role in creating West Virginia. The region's only major railroad before the Civil War, it helped towns grow, gave people jobs, and supported the Union during the War, which helped West Virginia become a state. The railroad began in 1827 and was the first to carry both people and freight in the U.S. It reached key places like Harpers Ferry (1836) and Wheeling (1853), but building through the mountains was slow and expensive.

During the Civil War, the B&O was damaged but quickly repaired by workers, many from West Virginia. After the war, the railroad expanded across the Midwest and grew to over 1,700 miles by 1884. However, borrowing too much money and competition from other railroads hurt its profits. A major strike started in Martinsburg in 1877 because of wage cuts.

The B&O later bounced back, adding more routes in West Virginia and modernizing its system in the early 1900s. But the Great Depression and new competition weakened it again. By 1973, the B&O had merged with other railroads into what is now CSX.