Section In section, the typical aisled church or cathedral has a nave with a single aisle on either side. The nave and aisles are separated by an arcade carried on piers or on columns. The roof of the aisle and the outer walls help to buttress the upper walls and vault of the nave, if present. Above the aisle roof are a row of windows known as the clerestory, which give light to the nave. During the Romanesque period there was a development from this two-stage elevation to a three-stage elevation in which there is a gallery, known as a triforium, between the arcade and the clerestory. This varies from a simple blind arcade decorating the walls, to a narrow arcaded passage, to a fully developed second story with a row of windows lighting the gallery.
Section I:n section, the typical aisled church or cathedral has a nave with a single aisle on either side. The nave and aisles are separated by an arcade carried on piers or on columns. The roof of the aisle and the outer walls help to buttress the ?upper walls and vault of the nave, i,f present. Above the aisle roof are a row of windows kno.wn as the clerestory, which give light to the nave. During the Romanesque period there was a development from this two-stage elevation to a three-stage elevation in which there is a gallery, known as a t.riforium, between the arcade and the clerestory. This varies from a simple blind arcade decorating the walls, to a narrow arcaded passage, to a fully developed second story with a row of windows lighting the gallery.