Great Mosque of Córdoba
Known locally as Mezquita-Catedral, the Great Mosque of Córdoba is one of the oldest structures still standing from the time Muslims ruled Al-Andalus in the late 8th century. The mosque-cathedral's hypostyle hall dates from the original mosque construction and originally served as its main prayer space for Muslims. The double-tiered arches were an innovation that permitted higher ceilings than would otherwise be possible with relatively low columns. The voussoirs of the arches alternate between red brick and white stone.
