As American factories and farms churned out more goods, legislators and businessmen created faster and cheaper ways to get those products to consumers. Around 1820, they began constructing a massive system of canals and roads linking states along the Atlantic coast with new states in the trans-Appalachian west. This transportation system set in motion both a crucial Market Revolution and a massive migration of people to the Greater Mississippi River basin. This huge area, drained by six river systems (the Missouri, Arkansas, Red, Ohio, Tennessee, and Mississippi), contains the largest and most productive contiguous acreage of arable land in the world. By 1860, nearly one-third of the nation’s citizens lived in eight of its states — the “Midwest,” consisting of the five states carved out of the Northwest Territory (Ohio, Indiana, Illinois, Michigan, and Wisconsin) along with Missouri, Iowa, and Minnesota. There they created a rich agricultural economy and an industrializing society similar to that of the Northeast.