A once-natural river
flowing through the heart of Chicago
. Notable as the gateway to an early and much-used portage
between the Great Lakes
and the Illinois River
(which flows into the Mississippi River
The Chicago River flowed into Lake Michigan until 1900 when, in a then-unrivalled feat of engineering, the Chicago Sanitary and Ship Canal and North Shore Channel were built to free the lake (source of drinking water for the region) of Chicago's sewage. Since that time, the river has flowed from the lake through the canal, emptying eventually into the Gulf of Mexico.
In modern times, the River is famous for being dyed green every year for the St. Patrick's Day parade. Pollution had reached a critical state in the 1970s but conservation and reclamation efforts have brought fish and wildlife back. In the 1990s the City began to develop riverfront walkways and space for tourism-related activities which now include waterbike rentals, excursion boats, riverfront cafés and eateries.