Heading for our condo on Longboat Key, Florida, we left Columbia this morning and drove east on I-70, undulating across the southern edge of the Glaciated Plain and crossing numerous streams that drain southward into the Missouri River. On the outskirts of St. Louis, we crossed the Missouri itself and then the Mississippi River, just south of the Arch.
Angling southeast on I-64, we left the Mississippi floodplain and travelled across the flat, rural landscape of central Illinois, fording the wooded channel of the Kaskaskia en route. South of Mt. Vernon, we switched to I-57 and then I-24, winding through the scenic Shawnee Hills, capped with Pennsylvanian sandstone, and eventually crossed the broad Ohio at Paducah, Kentucky. Curving eastward, we passed over the lower Tennessee and Cumberland Rivers (just north of Land Between the Lakes) and then angled to the southeast, traveling across the karst plain of Western Kentucky, a limestone region with numerous springs and caverns but few large surface streams. Once in Tennessee, we crossed the Red River (a tributary of the Cumberland) south of Clarksville and, nearing Nashville, entered the westernmost portion of the Appalachian Plateau, locally known as the Cumberland Plateau.
Approaching downtown Nashville, we switched to I-65, crossed the Cumberland River and headed south through the heavily dissected plateau toward Alabama. Our final and most spectacular river crossing would come southwest of Huntsville, near Decatur, where the highway arches above Wheeler Lake, on the Tennessee River, bounded by the rich wetlands of Wheeler National Wildlife Refuge. Leaving the Appalachian Plateau and entering the Ridge and Valley Province, we snaked through Birmingham and will spend the night south of that city. Tomorrow, on to Southwest Florida.
