Carlyle is a city in Clinton County, Illinois, United States. The population was 3,406 at the 2000 census. It is the county seat of Clinton County.
Carlyle is located approximately 50 miles east of St. Louis, Missouri, and is home to Illinois' largest man-made lake, Carlyle Lake, and to the General Dean Suspension Bridge, a suspension bridge that is the only one of its kind in Illinois and crosses the Kaskaskia River.
In 1811 or 1812 a man named John Hill built one of several “block” houses along the Goshen Trail, located at what is currently 201 Fairfax Street. The houses were reportedly built to serve as a line of defense against Native Americans. John Hill built what became the first house to be located in what Carlyle has become. He also established what could be considered Carlyle’s first business: a ferry to carry traffic across the Kaskaskia River, including a small shelter at the River which served as a toll house.