The pointed arch, one of the defining attributes of Gothic, was earlier incorporated into Islamic architecture following the Islamic conquests of Roman Syria and the Sassanid Empire in the Seventh Century. The pointed arch and its precursors had been employed in Late Roman and Sassanian architecture; within the Roman context, evidenced in early church building in Syria and occasional secular structures, like the Roman Karamagara Bridge; in Sassanid architecture, in the parabolic and pointed arches employed in palace and sacred construction.