The Roman arch avoided tension fully, maintaining all of the masonry in compression, from the keystone to your piers. Stone in compression has good strength, and the Romans crafted enormous arched bridges and aqueducts in huge quantities. Extending their arch into a tunnel, they invented the barrel vault, with which https://vymaps.com/US/West-Hills-Masonry-VN23008/?id_new=91f028d46d98c5b158f38e36720f8a1f