The Edwards River is a 73.7 miles (118.6 km) tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Mississippi River

Mississippi River

The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...

 in northwestern Illinois

Illinois

Illinois is the fifth-most populous state of the United States of America, and is often noted for being a microcosm of the entire country. With Chicago in the northeast, small industrial cities and great agricultural productivity in central and northern Illinois, and natural resources like coal,...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. It rises 3 miles (5 km) west of Kewanee

Kewanee, Illinois

Kewanee is a city in Henry County, Illinois, United States. "Kewanee" is the Winnebago word for prairie chicken, which lekked there. The population was 12,916 at the 2010 census, down from 12,944 at the 2000 census.-Geography:...

 in southeastern Henry County

Henry County, Illinois

Henry County is a county located in the U.S. state of Illinois. According to the 2010 census, it has a population of 50,486, which is a decrease of 1.0% from 51,020 in 2000. Its county seat is Cambridge...

 and flows generally westwardly into Mercer County

Mercer County, Illinois

Mercer County is a county located in the U.S. state of Illinois. According to the 2010 census, it has a population of 16,434, which is a decrease of 3.1% from 16,957 in 2000. Its county seat is Aledo...

, where it joins the Mississippi 2 miles (3 km) southeast of New Boston

New Boston, Illinois

New Boston is a city in Mercer County, Illinois, United States. The population was 632 at the 2000 census.-Geography:New Boston is located at ....

. In Henry County it collects the South Edwards River, which flows past Bishop Hill

Bishop Hill, Illinois

Bishop Hill is a village in Henry County, Illinois, along the South Edwards River. The population was 128 at the 2010 census, up from 125 at the 2000 census...

.

The river was once home to a grain mill near Andover, Illinois. Several sections of the Edwards River's course have been straightened and channelized.