As one drives northward across the Piedmont of central Alabama, prominent ridges are noted in Metro Birmingham. These represent the southern end of the Ridge and Valley Province of the Appalachians.
North of the city, Interstate 65 negotiates the southern end of the Appalachian Plateau, dipping, rising and curving through this heavily dissected terrain. Along the northern edge of the Plateau is the broad valley of the Tennessee River; the highway crosses this major stream within Wheeler National Wildlife Refuge, where, on cue, a pair of sandhill cranes cruised above our vehicle.
North of the river's floodplain, an appealing topography of low hills and ridges border the Interstate, drained by the Elk and Duck Rivers of Southern Tennessee; flowing westward, they are major tributaries of the Tennessee River, which curves northward toward the Ohio. The Duck River, designated a Wild and Scenic River, is the longest stream totally within the State of Tennessee.
See also: The Western Appalachians