Douglas County is a county in Illinois. It covers 417 square miles (267,162 acres), which represents less than one percent of the state total. Of Illinois's 102 counties, Douglas County ranks 58th in terms of the size of its population (19,823, according to 2015 Census estimates). Manufacturing and related services provide the main economic inputs to Douglas County. Recent Lands of America data shows that the average price-per-acre value of land for sale in Douglas County is $14,900. On average, the price of land for sale was $230,354 and the median acreage of land for sale in Douglas County was 15 acres. Land for sale in Douglas County totaled 15 acres and $230,354 in overall land value, with the city of Murdock featuring the most land for sale in the county. Farmland was the most common type of land for sale in Douglas County.