Southern Illinois the Ozarks of Missouri, is chiefly in southern Jackson, Union, northern Alexander and Johnson counties. The eastern area, more closely related to the Wabash Valley Seismic Zone, is mostly in northern Pope, southern Saline, Gallatin, eastern Johnson and southern Williamson counties. The Shawnee National Forest covers a large territory, including seven wilderness areas: Garden of the Gods, Bay Creek, Clear Springs, Bald Knob, Burden Falls, Lusk Creek, and Panthers Den. Of southern Illinois' rivers, only the Mississippi and the Ohio are navigable for modern commerce. The Big Muddy River, Marys River, Saline River and Cache River run their courses in
Olifants River (Southern Cape) the east and flows westwards between the Swartberg and Kammanassie mountains to its confluence with the Gamka River. The southern slopes of the Swartberg Mountains are drained by the perennial Groot River, Kango River, Grobbelaars River, Wynands River, Kansa River and Vlei River tributaries, which flow into the Olifants River. The Kammanassie River rises in the Outeniqua and Kammanassie mountains near Uniondale and joins the Olifants River upstream of Oudtshoorn. Olifants River (Southern Cape) Olifants River () is a river in the Klein Karoo area of the Western Cape, South Africa. It has its origins in the Traka and Kalkwal