Vandalia is a city located in Fayette County, in the state of Illinois (IL), United States. Nestled in the East North Central division of the Midwest region, it covers an area of 5.7 square miles (15.0 km²) and sits at an elevation of 515 ft. With a population of approximately 6,975 residents, Vandalia offers a peaceful, rural atmosphere.
The town's population is composed of about 57.33% males and 42.67% females, and it has a population density of 232.33 people per square mile (475.81/km²). Vandalia lies at a latitude of 38.97 and a longitude of -89.1, operating in the UTC-6.
Locals reflect a blend of American ancestry, with roots primarily in United States (10.4%), followed by English (10%), German (21.6%), and Scotch-Irish (0%) heritage. The town is identified by the ZIP code 62471.