The Butterfield Overland Mail was a stagecoach service that operated from 1858 to 1861, providing mail delivery between St. Louis, Missouri and San Francisco, California. It was established to connect the eastern United States with the West, facilitating communication and commerce during a time of rapid expansion. The route covered approximately 2,800 miles and took about 25 days to complete. The service was crucial for the movement of mail, people, and goods, especially during the California Gold Rush. However, it was eventually replaced by the Transcontinental Railroad, which offered a faster and more efficient means of transportation.