Lee County, Illinois, USA
County or equivalent
Location overview
Lee County lies in north-central Illinois, with Dixon as its county seat and the Rock River crossing its northern half. Glacial plains, fertile farmland, wooded river corridors and small towns give the county a predominantly rural landscape. Settlement began near present-day Dixon in 1828, and the county was created in 1839; railroads later accelerated the growth of farming communities such as Amboy and Franklin Grove. Lee County had about 32,900 residents in 2025. Agriculture remains central to its economy, joined by manufacturing, food processing, health care, renewable energy and tourism tied to the Rock River and Dixon’s historic sites.