<P> Judah returned to California in 1860 . He continued to search for a more practical route through the Sierra suitable for a railroad . In mid-1860, local miner Daniel Strong had surveyed a route over the Sierra for a wagon toll road, which he realized would also suit a railroad . He described his discovery in a letter to Judah . Together, they formed an association to solicit subscriptions from local merchants and businessmen to support their proposed railroad . </P> <P> From January or February 1861 until July, Judah and Strong led a 10 - person expedition to survey the route for the railroad over the Sierra Nevada through Clipper Gap and Emigrant Gap, over Donner Pass, and south to Truckee . They discovered a way across the Sierras that was gradual enough to be made suitable for a railroad, although it still needed a lot of work . </P> <Dl> <Dd> Main articles: The Big Four and Central Pacific Railroad </Dd> </Dl> <Dd> Main articles: The Big Four and Central Pacific Railroad </Dd>

Where did the railroad start in the east