Architectural terms: Triforium

In church architecture, the triforium {try-fohr'-ee-uhm} is the second of three stories in the nave walls; it is a galleried walkway above the arcade of the side aisles and below the clerestory. It seems to have been introduced in Romanesque churches in Italy and France (see Romanesque Art and Architecture) and was a regular feature in Gothic churches (see Gothic Art and Architecture) until the Late Gothic period (16th century). The triforium was windowless except in some Early Romanesque and Middle Gothic churches. The blind triforium in Chartres Cathedral is typical.

Source: 2001 Grolier Multimedia Encyclopedia, ©2000 Grolier Interactive Inc. — All Rights Reserved.
Bibliography: G. H. Cook, Medieval Chantries and Chantry Chapels, rev. ed. (1963; out-of-print); Louis Grodecki, Gothic Architecture (1985); Anthony Jones, Welsh Chapels (1996).
Relevant publications: Robin S. Oggins, Cathedrals (1996). Otto von Simson, The Gothic Cathedral: Origins of Gothic Architecture & the Medieval Concept of Order (1988). Stan Parry, Great Gothic Cathedrals of France (2001).
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