ARCADE

in architecture, a series of arches carried by columns or piers, a passageway between arches and a solid wall, or a covered walkway that provides access to adjacent shops. An arcade that supports a wall, a roof, or an entablature gains enough strength from lateral thrusts that each individual arch exerts against the next to carry tremendous weight loads and to stretch for great distances. Ancient aqueducts show an early use of the arcade. Later Roman builders used the pattern to construct large wall surfaces: the Colosseum, with 80 arcaded openings on each of its three stories, is one of the finest examples of this architectural form. An arcade with pilasters, or engaged columns attached to piers carrying an entablature, is known as a Roman arcade. During the late empire this was replaced by arches that rested on the capitals of a row of columns, a style that was standard in the Romanesque and Gothic periods and that was revived and widely used during the Renaissance (e.g., Filippo Brunelleschi's Ospedale degli Innocenti in Florence). In Byzantine arcades, spreading blocks called impost blocks were often placed between the capitals and arches, a style used widely throughout the East. As a purely decorative element, arcades are used in Gothic churches to divide the nave wall into three horizontal partsthe arcade at floor level, the triforium above, and the clerestory at the topas well as to frame sculpture on the facade (as can be seen, with excellent effect, on Amiens cathedral). To a lesser extent, Baroque architects made use of this form of the arcade, and it remained a significant element in Europe and America throughout the 19th century. As a covered passageway, the arcade has been in use since Roman times. Medieval cloisters often featured arcades, and most Islamic mosques include arcaded courtyards. In Renaissance towns such as Bologna, arcades line shops and other buildings. Middle Eastern bazaars are often arcaded rows of shops, and the design of modern enclosed or partially enclosed shopping centres has made the use of the label, if not the original form, common in the United States.