Cortland is an incorporated town in DeKalb County, Illinois, United States. The population was 4,270 at the 2010 census, up from 2,066 in 2000. Because of its status as an incorporated town, Cortland has adopted the slogan, “The Third Largest Town in Illinois”. Only the towns of Cicero and Normal are larger, in terms of population. A post office called Cortland has been in operation since 1892. The town was named after Cortland, New York.Cortland is located at 41°55′29″N 88°41′35″W (41.924857, -88.693093).According to the 2010 census, Cortland has a total area of 3.638 square miles (9.42 km2), of which 3.63 square miles (9.40 km2) (or 99.78%) is land and 0.008 square miles (0.02 km2) (or 0.22%) is water.
The town is located immediately east of the city of DeKalb and just south of the city of Sycamore. As of the census of 2000, there were 2,066 people, 701 households, and 553 families residing in the town. The population density was 1,176.3 people per square mile (453.2/km2). There were 723 housing units at an average density of 411.6 per square mile (158.6/km2). The racial makeup of the town was 95.11% White, 1.21% African American, 0.05% Native American, 1.26% Asian, 0.97% from other races, and 1.40% from two or more races. Hispanic or Latino of any race were 4.40% of the population.
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