Threeaisled

Three-aisled, or triple-aisled, describes a building plan in which the interior space is divided into three parallel longitudinal areas: a central nave flanked by two side aisles. The aisles are typically separated from the nave by rows of columns or piers forming arcades, and the nave is usually higher, allowing for clerestory windows that illuminate the central space. The side aisles may be roofed at the same height as the nave or lower, depending on the design.

Origin and use: The three-aisled plan is a standard form in Christian church architecture from late antiquity through the medieval period. It is especially common in Romanesque and Gothic churches, where the arrangement supports processions, seating, and liturgical function. In many examples the nave, aisles, and occasional transept create a cruciform layout, while other implementations extend the aisles the full length of the building.

Variations: In some churches the nave and aisles are of roughly equal height, producing a hall church appearance and reducing the vertical emphasis of the clerestory. In other cases the aisles remain lower than the nave, preserving a clear clerestory. The three-aisled plan has also been used in secular buildings such as large halls and market structures.

See also: Basilica (architecture); Hall church; Nave; Aisle.