Marys River (Illinois) River basin: Marys River (Illinois) Marys River is a tributary of the Mississippi River in Illinois. It drains a small watershed between the Big Muddy River and the Kaskaskia River. It joins the Mississippi just southeast of Chester, near Kaskaskia. Because of its proximity to Kaskaskia — the capital of Illinois Territory and the first capital of the State of Illinois — Marys River was the site of early settlements leading into the interior of Illinois. Marys River is approximately in length. The following cities and towns are in the Marys River basin: Parts of the following counties are in
Big Muddy Creek (Missouri River tributary) Fort Peck Indian Reservation. It joins the Missouri west of Culbertson. It was explored in 1805 by the Lewis and Clark Expedition, who called it Martha's River in their journals and noticed on their return voyage in 1806 that it had changed its mouth on the Missouri. Along with the Milk River and the Poplar River, it is one of three waterways in Canada that drain into the Gulf of Mexico. Big Muddy Creek has also been known as: Big Muddy River, Little Yellow River, Martha River, Martha's River, Marthas River, Marthy's River and Park River. Big Muddy Creek (Missouri