Part 1 of Essay
Overland pioneer route to the northwestern United States. About 3200 km, about 2000 mi long, the trail extended from Independence, Missouri, to the Columbia River in Oregon. Part of the route followed the Platte River for 870 km (540 mi) through what is now Nebraska to Fort Laramie in present-day Wyoming. The trail continu ....

Part 2 of Essay
.... routes in the United States, sections of the had been used by the Native Americans and trappers. As early as 1742, part of the trail in Wyoming had been blazed by the Canadian explorer Pierre Gaultier de Varennes, sieur de La Vérendrye; the Lewis and Clark Expedition, between 1804 and 1806, made more of it known. The German-American fur trader and financier John Jacob Astor, in establishing his trading posts, dispatched a party overland in 1811 to follow the trail of these explorers. Later, mountain men such ....