STS040-152-127 Potomac River, Appalachian Mountains, West Virginia/Maryland, U.S.A. June 1991 The Potomac River flows southeastward (left center to lower right) across this north-looking low-oblique view. South of the Potomac near the center of the image, is the northern extension of the Shenandoah River Valley of Virginia and West Virginia. North of the Potomac River is the southwestern extension of the Cumberland Valley of Maryland and Pennsylvania. To the west (left) of the Shenandoah and Cumberland Valleys are the gently rolling, folded Appalachian Mountains, covered by the most varied deciduous forest in North America. To the east of the Shenandoah and Cumberland Valleys are the linear Blue Ridge Mountains. The valleys between the folded mountains are fertile agricultural regions.