Most cities with sizable Muslim populations possess a primary congregational mosque. Diverse in design and dimensions, they can illustrate the style of the period or geographic region, the choices of the patron, and the expertise of the architect. Congregational mosques are often expanded in conjunction with the growth and needs of the umma, or Muslim community; however, it is uncommon for such expansion and modification to continue over a span of a thousand years. The Great Mosque of Isfahan in Iran is unique in this regard and thus enjoys a special place in the history of Islamic architecture. Its present configuration is the sum of building and decorating activities carried out from the 8th through the 20th centuries. It is an architectural documentary, visually embodying the political exigencies and aesthetic tastes of the great Islamic empires of Persia.
Another distinctive aspect of the mosque is its urban integration. Positioned at the center of the old city, the mosque shares walls with other buildings abutting its perimeter. Due to its immense size and its numerous entrances (all except one inaccessible now), it formed a pedestrian hub, connecting the arterial network of paths crisscrossing the city. Far from being an insular sacred monument, the mosque facilitated public mobility and commercial activity thus transcending its principal function as a place for prayer alone.
The mosque’s core structure dates primarily from the 11th century when the Seljuk Turks established Isfahan as their capital. Additions and alterations were made during Il-Khanid, Timurid, Safavid, and Qajar rule. An earlier mosque with a single inner courtyard already existed on the current location. Under the reign of Malik Shah I (ruled 1072-1092) and his immediate successors, the mosque grew to its current four-iwan design. Indeed, the Great Mosque of Isfahan is considered the prototype for future four-iwan mosques (an iwan is a vaulted space that opens on one side to a courtyard).
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