One Bay, Nave of Lucca Cathedral
The Cathedral of St Martin (Italian Duomo) is a church in Lucca, Italy. It was begun in 1063 by Bishop Anselm (later Pope Alexander II). Of this structure, the great apse with its tall columnar arcades and the fine campanile remain. A bay is a module in classical or Gothic architecture, the distance between two supports of a vault or the unit of an opening and its framing on a façade.
A. D. F. Hamlin College Histories of Art History of Architecture (New York, NY: Longmans, Green, and Co., 1915)