Mount Vernon is a city in and the county seat of Posey County, Indiana, United States, in the state's far southwestern corner. The population was 7,478 at the 2000 census. It is located in Black Township and is part of the Evansville, Indiana, metropolitan area, which had a 2000 population of 342,815. According to the 2010 census, the city has a total area of 2.86 square miles (7.4 km2), of which 2.81 square miles (7.3 km2) (or 98.25%) is land and 0.05 square miles (0.13 km2) (or 1.75%) is water.
Evansville Western Railway, a short line railroad serving area industries both in Indiana and Illinois is headquartered in Mt Vernon.
Port of Indiana-Mount Vernon, a major publicly-funded riverport, is located just east of Mt. Vernon. It began operation in 1976 as Southwind Maritime Center and is one of three public ports operated by the state of Indiana.
The city and southern half of Posey County are served by the M.S.D. of Mount Vernon which currently operates 5 schools:
Mount Vernon Senior High School (9-12)
Mount Vernon Junior High (6-8)
Farmersville Elementary School (K-5)
Marrs Elementary School (K-5)
West Elementary School (K-5)
St Matthew's School (K-5) is operated under the auspices of the Diocese of Evansville