Savanna is a city in Carroll County, Illinois, United States. The population was 2,945 at the 2010 census, down from 3,542 in 2000. Savanna is located along the Mississippi River at the mouth of the Plum River. Going from north to south, the second automobile bridge between Iowa and Illinois is located just north of Savanna, and is part of U.S. Route 52. The bridge leads to Sabula, Iowa, which is across the river from Savanna. Savanna is also served by two major railroads, the Burlington Northern and Santa Fe Railway (BNSF) Railway Company and the (CP) Canadian Pacific. Savanna also has a small airport, the Tri-Township Airport (KSFY).