The designation “chapel” derives from the place that housed the royal Frankish relic, namely, half of the cape (Lat. cappella) of St. Martin of Tours (ca. 316–97). Although chapels conceived as sacred spaces in citadels and castles were actually part of the overall concept, independent cultic spaces, normally with an altar, were also called chapels (e.g., baptismal chapels, baptisteries, funerary chapels) and were constructed usually in the shape of a cross or as a central edifice. The initial architectonic result of the veneration involving altars (Saints, Veneration of), inf…