Before 1869 the only way for people to get around was either by foot or walking and that took way to long.
Then someone had an amazing idea that there should be a railroad built and then on it had been a plan. Then president Lincoln adopted the idea and potentially made it happen before he died.
The Transcontinental Railroad started in the 1860's. It was easier to ship people in from china instead of across the U.S. So the people building the railroad were Chinese. They were also a better pick because the government could pay them less.
The workers went through many different obstacles. Everyday was a life or death situation. Especially when they ran into mountains. So they went in with TNT and had to hope they could run out in time before it exploded.
After all of the struggles it was worth it in the end. In 1869, the Transcontinental Railroad was done and working.
The fully built Transcontinental Railroad runs from the central pacific and the union pacific. To this day we have railroads in the U.S because of the Transcontinental Railroad and we still use them as a form of transportation.