to become the state capital of Illinois, but lost by one vote to Vandalia in 1819. In 1824, Clinton County was formed, and Carlyle became the county seat in July 1825, both at the initiative of Charles Slade. Geography Carlyle is located slightly east of the center of Clinton County at (38.612642, -89.370789). The Kaskaskia River flows through the easternmost part of the city out of Carlyle Dam, located just northeast of the city limits and which impounds Carlyle Lake, the largest lake wholly in Illinois. U.S. Route 50 passes through the city, leading east to Salem and west to St. Louis. Illinois Route 127 leads north to Greenville and south to Nashville, Illinois. The General Dean Suspension Bridge, built in 1859 and named after Major General William F. Dean in 1953, crosses the Kaskaskia River just north of the current US 50 bridge. According to the 2021 census gazetteer files, Carlyle has a total area of , of which (or 99.97%) is land and (or 0.03%) is water. Demographics As of the 2020 census there were 3,253 people, 1,442 households, and 1,041 families residing in the city. The population density was . There were 1,480 housing units at an average density of . The racial makeup of the city was 88.56% White, 3.90% African American, 0.31% Native American, 0.89% Asian, 0.86% from other races, and 5.47% from two or more races. Hispanic or Latino of any race were 2.34% of the population. There were 1,442 households, out of which 43.48% had children under the age of 18 living with them, 47.50% were married couples living together, 19.90% had a female householder with no husband present, and 27.81% were non-families. 24.48% of all households were made up of individuals, and 8.74% had someone living alone who was 65 years of age or older. The average household size was 2.71 and the average family size was 2.34. The city's age distribution consisted of 17.7% under the age of 18, 18.3% from 18 to 24, 22.9% from 25 to 44, 25% from 45 to 64, and 16.1% who were 65 years of age or older. The median age was 36.1 years. For every 100 females, there were 98.1 males. For every 100 females age 18 and over, there were 91.1 males. The median income for a household in the city was $54,750, and the median income for a family was $67,188. Males