Sequatchie Valley is a long, arrow-straight scenic slash into eastern North America’s Appalachian Plateau that divides the southern half of its Tennessee portion into unequal parts. The valley extends southwestward for about two hundred miles from its northern end in Cumberland County, Tennessee, to its southern terminus in Blount County, Alabama; only the northeastern seventy-five miles lie in Tennessee. Sequatchie Valley is only about five miles wide, on average, and ranges from approximately 1,000 to 1,500 feet deep. The straight, linear nature of the valley is not obvious when looking up from its depths because the valley walls slope away from the bottom and are deeply incised by impressive tributary valleys, but when seen on a map or viewed from the air, it is very obvious.
Paralleling Sequatchie Valley and forming its southeast wall is Walden Ridge, the narrower of the two unequal parts into which the valley divides the Appalachian Plateau. Walden Ridge is also a relatively narrow, linear feature, but wider than the valley, averaging about eight to ten miles wide and generally rising to 2,000 feet in elevation. The ridge is almost coextensive with the Tennessee part of the valley, extending from Cumberland and Roane counties in the north to the Tennessee River gorge just north of the Tennessee-Georgia-Alabama juncture. The part of the plateau northwest of the Valley is called the Cumberland Plateau, and it is wider but more dissected than Walden Ridge, especially along its western edge. North and northeast of the valley the merged, much broader plateau is called the Cumberland Plateau. In this area, the steep escarpment along the eastern edge of the plateau all the way northeastward to beyond Lake City in Anderson County is called Walden Ridge.