Rockford is its third-largest city
[DOC] [TLE] Rockford, Illinois - Wikipedia [PAR] Rockford is the third largest city in the U.S. state of Illinois, the 171st most 
populous city in the ... Its decline, emblematic of other cities in the Rust Belt, led to 
economic diversification into automotive, aerospace, and healthcare industries, 
as well... [DOC] [TLE] 5 Biggest Cities in Illinois: How Well Do You Know the Prairie State?