A plantation house is the main house of a plantation, often a substantial farmhouse, which often serves as a symbol for the plantation as a whole. The cited article says plantation houses in the Southern United States and in other areas are known as quite grand and expensive architectural works today, though most were more utilitarian, working farmhouses. The buildings recorded in the atlas under the plantation heading are the houses and working buildings of such estates, and the term names the kind of dwelling that stands at the centre of an agricultural estate. Buildings recorded in the atlas as plantations are grouped under this concept.