ARCHES

ARCH is a curved structure that spans a space and may or may not support weight above it.^[1] Arch may be synonymous with vault but vault may be distinguished as a continuous arch^[2] forming a roof. Arches appeared as early as the 2nd millennium BC in Mesopotamian brick architecture^[3] and their systematic use started with the Ancient Romans who were the first to apply the technique to a wide range of structures.