Vandalia is a city in northeastern Audrain and extending into southeastern Ralls Counties in the U.S. state of Missouri.

[5] The Audrain County portion of Vandalia is part of the Mexico Micropolitan Statistical Area, while the Ralls County portion is part of the Hannibal Micropolitan Statistical Area.

Vandalia was laid off by Aaron McPike and Judge Harmen Caldwell in 1870 [6] and platted in 1871.

[8] Aaron McPike transferred the lumber used to build the first homes from Louisiana, Missouri.

[9] The Lincoln School was listed on the National Register of Historic Places in 1996.

[10] Vandalia is located on US Route 54 in the northeastern corner of Audrain County about 15 miles west of Bowling Green.

U.S. Route 54 connects Vandalia with Illinois to the east and Jefferson City and the Lake of the Ozarks to the south and west.

34.3% of all households were made up of individuals, and 16.1% had someone living alone who was 65 years of age or older.

[17] The United States Postal Service operates the Vandalia Post Office.