The town of Plainville is located in the southwestern part of Hartford County. Originally a part of Farmington, the town was incorporated as a separate town in 1869. In the early references, this area was mentioned as Great Plain, which became the basis of the current name. The local industry started after the Farmington Canal opening in 1828. Shortly after that, warehouses, taverns, and factories became an important part of the town’s economy. However, the canal grew obsolete, and the railroad took its place. Also, the oldest airport in the state, the Robertson Airport, is located in Plainville.