Loudon is a city in and the county seat of Loudon County, Tennessee, United States. Its population was 5,381 at the 2010 census. It is included in the Knoxville, Tennessee Metropolitan Statistical Area. The city is located in East Tennessee, southwest of Knoxville, on the Tennessee River. Fort Loudoun, the colonial era fort for which the city was named, is located several miles to the south in Monroe County.
Loudon is located at 35°44′2″N 84°20′58″W (35.733856, -84.349417).
According to the United States Census Bureau, the city has a total area of 9.6 square miles (25 km2), of which 9.3 square miles (24 km2) is land and 0.3 square miles (0.78 km2) (3.42%) is water.
As of the census of 2010, there were 5,381 people, 1,910 households. The population density was 389.4 people per square mile (185.4/km2). There were 2,426 housing units. The racial makeup of the city was 83.2% White, 2.9% African American, 0.31% Native American, 0.2% Asian, 10.9% from other races, and 1.5% from two or more races.