The Corps of Discovery stopped at the site of the Historical Reserve. Lewis and Clark both made favorable comments about the area in their journals.

Here I landed and walked on Shore, about 3 miles a fine open Prarie for about 1 mile, back of which the countrey rises gradually and wood land comencies Such as white oake, pine of different kinds, wild crabs with the tast and favour of the common crab and Several Species of undergroth of which I am not acquainted, a few Cottonwood trees & the Ash of this countrey grow Scattered on the river bank . . .   –William Clark, November 4, 1805

This valley would be copetent to the mantainance of 40 or 50 thousand souls if properly cultivated and is indeed the only desireable situation for a settlement which I have seen on the West side of the Rocky mountains.   –Merriwether Lewis, March 30, 1806