Continental Divide

Continental Divide. . , You are standing on a Continental Divide. Water falling on this line separates and runs to the west and to the east. To the west the water flows to the Des Plaines River in River Forest, on to the Illinois and Mississippi Rivers and to the Gulf of Mexico. To the east, historically, the flow was to the Chicago River, to Lake Michigan, through the Great Lakes to the Atlantic Ocean. With the reversal of the flow of the Chicago River in 1900, all water now flows to the Gulf of Mexico. , , East of this line is a ridge which is the beach of ancient Lake Chicago. The high, dry ground formed by this ridge encouraged early settlement in Oak Park in 1837. , , Only one point along the entire length of the Continental Divide offered the possibility of a direct connection between the Great Lakes and Mississippi River watersheds. This point was on a route used by Native Americans for centuries and known to be shared in 1673 with French explorers Fr. Jacques Marquette and fur trader Louis Joliet. Located five miles south of Oak Park, today a portion is preserved as the Chicago Portage National Historic Site. This natural connection also made possible the Illinois and Michigan Canal (completed 1848) and the Sanitary and Ship Canal (completed 1900).