The sections of the transcontinental railroad join in california nebraska kansas utah

The sections of the Transcontinental Railroad joined together in Utah at a place called Promontory Point in 1869 where a famous photograph was taken of the two construction crew (minus the Asian workers who were forbidden from being in the photo) meeting and uniting the rail with a Golden Spike.

Railroads

Explanation: Railroads made it significantly easier to get raw materials (such as oil and steel) across the country. If you want a specific example, look at the Trans-Continental Railroad