What made the railroad expansion possible because thousands of miles of track were made of this?

The railroad expansion of the west was one of the greatest achievements in the history of construction. The construction began in 1863 when the government approved the project and financed approximately 60 million dollars at the time which was half of what was needed. The other 50% came from private investors.

Many materials were brought from the east, particularly the metal ones like the rail lines and the pieces which joined the trails. This made the task very difficult. However, the roadbed of the tracks was aimed to be made of stone and timber. Materials, that were accessible along the great majority of the route. This contributed to the feasibility of the project.