Which U.S. region was most impacted by the completion of the transcontinental railroad in 1869?

The Western United States was most impacted by the completion of the transcontinental railroad in 1869. This event helped to connect the East and West coasts of the country, making it easier and faster to travel and transport goods across the country. The completion of the railroad also led to increased settlement and economic growth in the Western states, as well as the depletion of Native American lands and culture.