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
Muddy River (Nevada) Muddy River (Nevada) The Muddy River, formerly known as the Moapa River, is a short river located in Clark County, in southern Nevada, United States. It is in the Mojave Desert, approximately north of Las Vegas. The Muddy River is approximately long. It begins as a series of thermal springs in the Moapa Valley before continuing on its course to Lake Mead, where it drains into the northern arm of the lake near Overton, Nevada. Before the Hoover Dam's construction, the Muddy River flowed into the Virgin River. Near the town of Glendale the Muddy River collects the flow from