Final answer:
The transcontinental railroad fueled industrial expansion, transformed the country by encouraging migration to urban centers, and played a role in important historical events.
Step-by-step explanation:
The transcontinental railroad had a major impact on the United States. It fueled industrial expansion, including the growth of steel manufacturing, the telephone, and the light bulb. The railroads also facilitated the transportation of vast mineral resources in the western states.
Additionally, the railroad system transformed the country by encouraging the migration from rural areas to urban centers, causing the decline of craft industries and the rise of factory work.
Furthermore, the transcontinental railroad contributed to economic growth and played a role in important historical events such as the internal destruction of Native Americans, the end of formal slavery, and the opening of lands for immigrants.