In architecture and city planning, a terraced or terrace house (UK) or townhouse (US) exhibits a style of medium-density housing that originated in Europe in the 16th century, where a row of identical or mirror-image houses share side walls. They are also known in some areas as row houses (specifically Philadelphia, Washington and Baltimore) or linked houses.
Terrace housing can be found throughout the world, though it is in abundance in Europe and Latin America, and extensive examples can be found in Northern America and Australia. The Place des Vosges in Paris (1605–1612) is one of the early examples of the style. Sometimes associated with the working class, historical and reproduction terraces have increasingly become part of the process of gentrification in certain inner-city areas.
Though earlier Gothic ecclesiastical examples, such as Vicars' Close, Wells are known, the practice of building new domestic homes uniformly to the property line really began in the 16th century following Dutch and Belgian models and became known in English as "row" houses. "Yarmouth Rows" in Great Yarmouth, Norfolk is an example where the building fronts uniformly ran right to the property line.
The term terrace was borrowed from garden terraces by British architects of the late Georgian period to describe streets of houses whose uniform fronts and uniform height created an ensemble that was more stylish than a "row". Townhouses (or townhomes) are generally two- to three-storey structures that share a wall with a neighbouring unit. As opposed to an apartment building, townhouses do not have neighbouring units above or below them. They are similar in concept to row houses or terraced houses, except they are usually divided into smaller groupings of homes. The first and last of these houses is called an end terrace, and is often a different layout from the houses in the middle, sometimes called mid-terrace.