Abstract
This paper presents a study on spatial construction in relation to chants and cathedrals in the medieval period. First, studies on musical space in relation to visual space are surveyed. The gestalt notions of figure and ground are then described. These are used as a basic tool for an analysis of how cathedral arches of the nave were assembled vertically with regard to musical sound. From a formal analysis it is found that the vertical spatial construction of chants and that of naves in medieval cathedrals display a similar pattern.