Pennsylvania Germans near the Conestoga River first made Conestoga wagons around 1750 to haul freight. By the 1810s, improved roads to Pittsburgh and Wheeling, Virginia (now West Virginia) stimulated trade between Philadelphia, Baltimore, and settlers near the Ohio River. Wagoners with horse-drawn Conestoga wagons carried supplies and finished goods westward on three- to four-week journeys and returned with flour, whiskey, tobacco, and other products. The Conestoga wagon’s curved shape shifted cargo toward the center and prevented items from sliding on mountain slopes. Railroads replaced Conestoga wagons by the 1850s, but the prairie schooner, a lightweight, flat variant, carried pioneer settlers from Missouri to the West Coast.