The Denver and Rio Grande Railroad (D&RG) was a significant American railroad established in 1870. It primarily served the western United States, connecting Denver, Colorado to various mining towns and facilitating the transport of goods and passengers. The D&RG played a crucial role in the development of the region, especially during the mining boom. In 1880, the railroad expanded its reach by merging with other lines, becoming the Denver and Rio Grande Western Railroad. This expansion allowed it to connect with the Southern Pacific Railroad and enhance trade and travel across the Rocky Mountains. The D&RG is known for its scenic routes and contributions to the growth of the American West.