where is vandalia missouri?
<answer> In Audrain and Ralls Counties in the U.S. state of Missouri. <context> Sponsored Topics. Vandalia is a city in Audrain and Ralls Counties in the U.S. state of Missouri. The population was 2,529 at the 2000 census. Col. Aaron McPike, who founded Vandalia in 1874, called Vandalia Queen of the Prairie. Vast rolling prairies had underlying coal and refractory types of clay.