The Illinois River is known by a few different names. One of the most common synonyms is "Father of Waters," which was given to the river by French explorers due to its size and importance. Another is the "Rio de Illinois," a Spanish variant of its original French name. Locals often refer to it as simply "the Illinois," or "IL River." The river originates in Wisconsin and flows through Illinois and Missouri, ultimately emptying into the Mississippi River. It is an important water source for many communities living along its banks, as well as an important transportation route for goods and services.