Arch

An arch is a curved vertical structure spanning an open space underneath it. Arch can either support the load above it or perform a purely decorative role. The arch dates back to fourth millennium BC, but became popular only after its adoption by the Romans in the 4th century BC.
Arch-like structures can be horizontal, like an arch dam that withstands the horizontal hydrostatic pressure load. Arches are normally used as supports for many types of vaults, with the barrel... meer