This detailed map is from Fremont's first expedition to the Rockies in 1842. It locates Medicine Bow Mountains, New Park Mountains, Wind River Mountains, the Laramie Plains, and St. Vrain's Fort and extends eastward to the confluence of the North and South forks of the Platte River. Fremont surveyed the Oregon Trail as far as South Pass and then explored the Wind River Range of the Rocky Mountains. These mountains form a portion of the Continental Divide and had been the subject of considerable spurious cartography prior to this exploration. Wheat describes the maps as "a highly creditable production" that is free of "imaginary geography." Fremont employed Kit Carson as a guide and Charles Preuss as a cartographer, and despite losing their barometer and other instruments when one of their rafts sank, the expedition was a success and launched Fremont into national prominence. The map is on two joined sheets, as issued. This map is a very nice example, as the map is normally found with considerable toning along folds and is always close trimmed at left.

References: Wheat (TMW) #464.

Condition: B+

Folding, as issued. The map is clean and bright with a fine impression and coloring. The left binding portion has paper added to facilitate framing with a portion of the neatline reinstated in facsimile and a tear from binding edge enters blank area (closed on verso with archival tape).