Clarksville is located in Clark county Indiana with a geographic area of 10.0 square miles. The total population in Clarksville is 21,825 with 47.6% male and 52.4% female. Children under age 5 represent 6.1% of the population, under age 18 equal 19.2% of the population and over age 65 is 17.3% of the population. The median household income is $46,931, per capita income is $27,467. There are a total of 8,993 housing units with 58.6% owner occupied. Education includes 34.4% of residents that are high school graduates and 16.8% with a bachelor's degree or higher. The average temperature in Clarksville in the summer is 73 degrees, and in the winter 29 degrees.