Niles Canyon is a canyon in the San Francisco Bay Area formed by Alameda Creek, known for its heritage railroad and silent movie history. The canyon is largely in an unincorporated area of Alameda County, while the western portion of the canyon lies within the city limits of Fremont and Union City. The stretch of State Route 84 known as Niles Canyon Road traverses the length of the canyon from the Niles district of Fremont to the unincorporated town of Sunol. Two railroads also follow the same route down the canyon from Sunol to Niles: the old Southern Pacific track along the north side, now the Niles Canyon Railway, and the newer Union Pacific (formerly the Western Pacific) track a little to the south. At the west end of the canyon are the ruins of the Vallejo Flour Mill, which dates to 1853. History The route of El Camino Viejo à Los Angeles (Old Road to Los Angeles), the oldest north-south trail in the interior of Alta California, ran through Niles Canyon. In addition, the canyon, then known as Alameda Cañon, was located in three different Mexican land grants - Rancho Arroyo de la Alameda, Rancho Ex-Mission San José, and Rancho Valle de San Jose. It was later named Cañada Molina Vallejo for the two-story adobe grist mill built in the early 1840s on the Rancho Arroyo de la Alameda near the mouth of the canyon by its owner José de Jesús Vallejo, elder brother of Mariano Guadalupe Vallejo. The locality became known as Vallejo's Mill and later as Vallejo's Mills when Vallejo built a second wooden three story mill next to the original adobe mill in 1856. The area later became the town of Niles, named after the Niles Station, which was built after the first transcontinental railroad was completed through the canyon by Western Pacific Railroad (1862-1870) in the Summer of 1869. The station was named after Central Pacific Railroad attorney Addison C. Niles, later a California Supreme Court judge. The Thompson & West map shows that the area was still known as Niles or Vallejo Mills in 1878 with the Contract & Finance Co., a subsidiary of Central Pacific, still in ownership of the later town of Niles. The railroad through Alameda Cañon to Pleasanton was completed August 15, 1869 and to Laddsville on August 18, 1869. The first through train from Sacramento to Alameda Terminal (the