A
barrel vault, also known as a
tunnel vault or a
wagon vault, is an architectural element formed by the extrusion of a single curve (or pair of curves, in the case of a pointed barrel vault) along a given distance. The curves are typically circular in shape, lending a semi-cylindrical appearance to the total design. The barrel vault is the simplest form of a
vault: effectively a series of
arches placed side by side, i.e., one after another. It is a form of
barrel roof.