This vector follows the official route of Lewis & Clark and Corps of Discovery from 1804-1806. This historic trail extends 3,700 miles, crossing 11 states from Illinois to Oregon. Historic channel data developed by James D. Harlan of the University of Missouri; Lewis and Clark overland trail data created by Steve F. Russell of Iowa State University; and Lewis and Clark Trail Maps produced by Martin Plamondon II. Data includes inbound and outbound information, leader of trail section, and whether overland or by river.