Known as "Warren's General Map," this is a monumentally important map that is considered to be the first accurate overall picture of the region. Wheat considered it so important that he dedicated eight pages to its description and called it the most important map produced by the Topographical Engineers. Drawn on the polyconic projection, the map culminated a half-century of government explorations beginning with Lewis & Clark. Only 24 years old when assigned the task, Warren used information from the U.S. Land Office, the Coast Survey, Topographical Engineers, the Adjutant General, the Quartermaster General, the Indian Bureau, and Smithsonian Institution to obtain the latest information in developing this map. The majority of the map was completed by 1854, but it was not fully complete when the first railroad survey report was published in 1855 and thus did not accompany all editions. A remarkable and scarce map that represents the best geological knowledge of the day. Printed on two sheets and joined, as issued.

References: Wheat (TMW) #936.

Condition: B

Issued folding with light scattered foxing and toning along the upper half of the map. There are several splits at fold intersections, along with a long fold separation and 7" binding tear at top left that have both been repaired on verso with archival tape. Trimmed to inside the neatline along parts of the left border.