During the 1850s, the U.S. government sponsored an extensive series of expeditions designed to gather information on the vast new territories that had been acquired in western North America. The discovery of gold in California further stimulated westward traffic and heightened the need for a faster and more convenient way to bring the far-flung parts of the country together. In 1853 Congress commissioned the Army's Topographic Bureau to conduct a series of surveys to find a suitable route for a transcontinental railroad. There were six major expeditions; five of them covered the area between the Great Plains and west coast, and the sixth explored the coastal states of California and Oregon. All of these expeditions were accompanied by naturalists and artists to document the landscape, flora and fauna along the route. The reports, maps and lithographs were published in the 13 volume report "Explorations and Surveys to ascertain the most practicable and economical route for a Railroad from the Mississippi river to the Pacific Ocean."

This detailed map of the region centers on Tejon Pass, including the Tulare Valley, and the Kern and Buenavista Lakes. Walker's Pass, Hum-pah-map Pass, Tah-ee-chay-pay Pass, Tejon Pass, Arroyo de las Uvas, Arroyo de San Arminio, and Fremont's route through the region are located. A wagon road through Tejon Pass and a new pass leading to Los Angeles are also identified, and topography is denoted through finely engraved hachure.

References: Wheat (TMW) #878.

Condition: B+

Issued folding, now flat and backed in tissue to repair some separations along the folds and a few small holes along the folds, with minor loss of image. There is a horizontal misfold and faint toning along the folds.