Chicago River, Chicago, Illinois

Chicago is built on Lake Michigan, but a river runs through it - the Chicago River. Beginning at Lake Michigan and flowing southward through the heart of the city, the river is crossed by numerous bridges and its banks are lined with skyscrapers.

The Chicago River, which runs for 156 miles, is notable for having reversed its direction in a famous civil engineering feat in the 19th century. The current was redirected to flow away from Lake Michigan, into which it previously emptied, and towards the Mississippi River basin. This was done for reasons of sanitation, to flush polluted water away from the city and the lake.

The river is also noted for the local custom of dyeing it green on St. Patrick's Day.Several vendors offer guided cruises on the river which is an excellent way to learn more about the city, its history and impressive architecture.