The Roman arch underwent a significant modification in the center Ages from the evolution on the pointed arch, which presented a strong skeleton resting on well-spaced piers. The large, rigid masonry constructions from the Romans gave way to soaring vaults supported by exterior flying buttresses (exterior bracing). Cite Although just https://ewr1.vultrobjects.com/blissdrive/westhillmasonry/Hardscape-Contractors.html