Calhoun, the seat of McLean county, is located on KY 81 at the Green River. It was established in 1785 by Henry Rhoads as Rhoadsville and was later known as Fort Vienna. In 1849 the town was named Calhoun (or Calhoon) for Judge John Calhoun. Calhoun was incorporated in 1852 and became the seat of McLean county when it was formed in 1854. The Calhoun post office opened in 1849. The population in 1990 was 854.
The first McLean County Courthouse was built about 1854. The present structure, the third, was completed in 1908.