City of Chicago Flag 

The flag of the city of Chicago, Illinois. 

The flag was adopted by the City Council on April 4, 1917. The flag was designed by Wallace Rice, a writer and lecturer at the Art Institute of Chicago.

Rice's design consists of two light blue stripes that cut across a white background to create three white stripes. Rice's original design featured only two six-pointed stars but two more were added in the 1930s. 

The first two stars added by Rice represent the Great Chicago Fire of 1871 and the 1893 World's Fair. The third and fourth stars represent Fort Dearborn and the Century of Progress Exposition of 1933-34. The white and blue colors represent the city's physical geography. The white stripes stand for the North, West, and South sides of the city while the top blue line represents Lake Michigan and the north branch of the Chicago River. The bottom blue line represents the south branch of the river and the Chicago Sanitary and Ship Canal. 

The stars have six points because they had never been on a flag before and they were “peculiarly and singularly a Chicago star,” according to Rice. 

The Chicago Flag is one of the most popular and well-known city flags in the US, coming in only behind the flag of Washington D.C. in a 2004 survey conducted by the North American Vexillological Association. 

Source: https://www.architecture.org/online-resources/architecture-encyclopedia/the-chicago-flag