True arches, as opposed to corbel arches, were known by a number of civilizations in the Ancient Near East and the Levant, but their use was infrequent and mostly confined to underground structures, such as drains where the problem of lateral thrust is greatly diminished [REF].
The segmental arch was first built by the Romans who realized that an arch in a bridge did not have to be a semicircle,[REF][REF] such as in Alconétar Bridge or Ponte San Lorenzo.