Great Appalachian Valley

The Great Valley, also called the Great Appalachian Valley or Great Valley Region, is one of the major landform features of eastern North America. It is a gigantic trough -- a chain of valley lowlands -- and the central feature of the Appalachian Mountain system. The trough stretches from Canada southwest to Alabama and has been an important north-south route of travel since prehistory.

In its northern section, the Great Valley includes the St. Lawrence River valley in Canada and extends west of the Appalachian ranges of Canada and New England, separating them from the Adirondack Mountains.

In its southern section, the Great Valley is regionally referred to as the Valley of Virginia. It is a sub-province of the Ridge and Valley physiographic province, bounded by the Blue Ridge Mountains on the east, and Great North Mountain on the west, and interrupted by Massanutten Mountain in Virginia. This portion can itself be subdivided into a string of river basins. From northeast to southwest, these are the Shenandoah Valley, the James River Valley, the Roanoke Valley, the New River Valley, the Holston River Valley, and the Cumberland, and Tennessee river valleys. The Valley of Virginia is a region of karst, with many sinkholes and caverns.

The Valley of Virginia includes rich farmland, especially in the valleys of the Cumberland and Shenandoah. It was a main route for settlement and commerce in the United States along the Great Wagon Road, which began in Philadelphia. The Wilderness Road into Kentucky and Tennessee branched off from the Great Wagon Road at present-day Roanoke, Virginia. Today, the main thoroughfare occupying the Valley of Virginia is Interstate 81.