Architectural folly

In architecture, a folly is a building constructed primarily for decoration, but suggesting through its appearance some other purpose, or of such extravagant appearance that it transcends the range of garden ornaments usually associated with the class of buildings to which it belongs.

Eighteenth-century English gardens and French landscape gardening often featured mock Roman temples, symbolising classical virtues. Other 18th-century garden follies represented Chinese temples, Egyptian pyramids, ruined abbeys, or Tatar tents, to represent different continents or historical eras. Sometimes they represented rustic villages, mills, and cottages to symbolise rural virtues. Many follies, particularly during times of famine, such as the Irish potato famine, were built as a form of poor relief, to provide employment for peasants and unemployed artisans.

In English, the term began as "a popular name for any costly structure considered to have shown folly in the builder", the OED's definition, and were often named after the individual who commissioned or designed the project. The connotations of silliness or madness in this definition is in accord with the general meaning of the French word "folie"; however, another older meaning of this word is "delight" or "favourite abode" This sense included conventional, practical, buildings that were thought unduly large or expensive, such as Beckford's Folly, an extremely expensive early Gothic Revival country house that collapsed under the weight of its tower in 1825, 12 years after completion. As a general term, "folly" is usually applied to a small building that appears to have no practical purpose, or the purpose of which appears less important than its striking and unusual design, but the term is ultimately subjective, so a precise definition is not possible.

The concept of the folly is subjective and it has been suggested that the definition of a folly "lies in the eyes of the beholder". Typical characteristics include:

Follies began as decorative accents on the great estates of the late 16th century and early 17th century but they flourished especially in the two centuries which followed. Many estates had ruins of monastic houses and (in Italy) Roman villas; others, lacking such buildings, constructed their own sham versions of these romantic structures.

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