The famous engineer known for his work on the Transcontinental Railroad was Greenville Dodge. As the chief engineer for the Union Pacific Railroad, he played an instrumental role in the construction of the railway system that connected the eastern and western United States. Dodge oversaw significant engineering challenges, including the construction of tunnels and bridges across rugged terrains. His efforts not only facilitated westward expansion and commerce but also transformed the American economy. The completion of the railroad in 1869 marked a significant milestone in American infrastructure and transportation history.