Big Muddy River the sides of hills, exposing coal deposits. The first coal mine in Illinois is believed to have been opened in 1810 on the banks of the Big Muddy in Jackson County. The Big Muddy cuts through the Shawnee Hills south of Murphysboro near the confluence with its smaller tributary, Kinkaid Creek. From there, it runs southward roughly twenty miles and meets the Mississippi directly south of Grand Tower. Near its mouth, a small portion of the Big Muddy acts as the dividing line between Jackson and Union counties. Major tributaries of the Big Muddy include Beaucoup Creek, the Little Muddy
Big Thompson River tributary flows east, through the town of Glen Haven, where it merges with the Big Thompson River in the town of Drake, in the Big Thompson Canyon. From Lake Estes, the river descends 1/2 mile (800 m) in elevation through the mountains in the spectacular 25 mi (40 km) Big Thompson Canyon, emerging from the foothills west of Loveland. It flows eastward, south of Loveland across the plains into Weld County and joins the South Platte approximately 5 mi (8 km) south of Greeley. It receives the Little Thompson River approximately four mi (6 km) upstream from its mouth. Water