Mosque, a building that serves as the main place of worship for Muslims. Mosques are of various sizes and types; the Friday mosque—in which the entire congregation assembles to perform the ritual Friday prayers—is by far the largest and most important. The great age of mosque building extends from the 7th century, when Islam was founded in Arabia, to the 16th century.
The first mosque was the courtyard of Muhammad’s own house in Medina (ad622), in present-day Saudi Arabia. The wall of the courtyard facing in the direction of the holy city of Mecca—called the qibla wall—was provided with a roofed area where prayers were recited; the other three walls were lined with shallow arcades. This scheme became the basic plan for all later mosque design, of which the three main elements continued to be the courtyard, the qibla wall, and the roofed prayer hall. In the center of the qibla wall is the mihrab, or prayer niche, that indicates the direction of Mecca. Next to the mihrab is the mimbar, a pulpit from which the Friday sermon is preached.
In religion-dominated Islamic societies, mosques serve social and political needs as well as religious ones. The mosque became a forum for many public functions, serving as a law court, school, assembly hall, and even as a parade ground. Adjoining chambers often house libraries, hospitals, or treasuries.
As Islam spread outside Arabia, mosque design gradually incorporated elements adapted from the architecture of conquered territories. Basilica-type mosques, such as the Great Mosque in Damascus (8th century), were based on Early Christian church design, which in turn was derived from pagan basilicas (see Basilica). In the basilica style, the prayer hall of the mosque was enlarged and expanded to accommodate an impressive flat.roofed nave and two parallel side aisles. The columns supporting the roof of the prayer hall often feature row upon row of round or lobed (horseshoe) arches (see Arch and Vault), as in the Mosque of Córdoba (8th to 10th century) in Spain. Decoration proliferated in the form of carving, inlay, tile, and painting. Islam forbade the representation of human or animal forms, however; hence these decorations took the form of geometric designs, birds, foliage, and arabesques.
In the earliest mosques, the call to prayer was given by the muezzin, or crier, directly from the roof of the mosque itself. The use of a minaret for the same purpose began with the Mosque of Al Qayraw?n (8th century) in Tunisia; the minaret is thought to have been an adaptation of the square towers of Early Christian churches in pre-Islamic Syria. Minarets became a common feature of nearly all later mosques; they are either round, square, spiral, or octagonal and range in shape from short and squat to tall and slender.
Mosques on the cruciform (cross-shaped) plan evolved in Iran during the 12th century, while domed mosques—the last and greatest innovation in mosque design—originated in Turkey after the Ottoman conquest of Constantinople (present-day ?stanbul) in 1453. The inspiration for the great Ottoman mosques was the vast Christian church of Hagia Sophia (532-37; Church of the Holy Wisdom) in Constantinople, whose innovative arch-and-dome structure made possible the use of large, light-filled domes to roof enormous spaces. Turkish mosques usually feature a prayer hall surmounted by a large central dome, in turn surrounded by smaller domes and half domes. As in Iranian mosques, the traditional courtyard often was eliminated entirely. The greatest Turkish mosque designer was the architect Sinan, who was credited with over 300 buildings. His masterpiece is the Süleymaniye Mosque (1550-57) in ?stanbul; its square central mosque, topped with a soaring light-filled dome, is supported on a complex system of arches, semidomes, and arcades, with four slim minarets set around the dome.