Mosque and religious complex in Istanbul, Turkey
The Süleymaniye Mosque (, ) is an Ottoman imperial mosque located on the Third Hill of Istanbul, Turkey. The mosque was commissioned by Suleiman the Magnificent (r. 1520 – 1566) and designed by the imperial architect Mimar Sinan. An inscription specifies the foundation date as 1550 and the inauguration date as 1557, although work on the complex probably continued for a few years after this. 
The Süleymaniye Mosque is one of the best-known sights of Istanbul and from its location on the Third Hill it commands an extensive view of the city around the Golden Horn. It is considered a masterpiece of Ottoman architecture and one of Mimar Sinan's greatest works. It is the largest Ottoman-era mosque in the city. 
Like other Ottoman imperial foundations, the mosque is part of a larger "külliye" (religious and charitable complex) which included madrasas, a public kitchen, and a hospital, among others. Behind the "qibla" wall of the mosque is an enclosed cemetery containing the separate octagonal mausoleums of Suleiman the Magnificent and his wife Hurrem Sultan (Roxelana).
History.
Construction.
Sultan Suleiman the Magnificent chose the architect Mimar Sinan to create a mosque in memory of his son Şehzade (Crown Prince) Mehmed. Suleiman was so impressed with the ensuing Şehzade Mosque (Şehzade Cami) that he asked Sinan to design a mosque for himself too. This mosque would represent the pre-eminence of the Ottoman Empire.
The mosque was built on the site of the old Ottoman palace ("Eski Saray") which was still in use at the time and had to be demolished. The Arabic inscription above the entrance to prayer hall gives a foundation date of 1550 and an inauguration date of 1557. In reality, the planning of the mosque began before 1550 and parts of the complex were not completed until after 1557. The final construction expenses were recorded in 1559, relating to some of the madrasas and to the mausoleum of Suleiman's wife, Hürrem Sultan (d. 1558). The mausoleum for Suleiman himself was built after his death on the orders of his son and successor, Selim II, between 1566 and 1568.
Marble spolia from various sites in Constantinople and other parts of the empire were reportedly gathered and shipped to the construction site. Petrus Gyllius, a contemporary observer, wrote about seeing one of the four enormous porphyry columns destined for the mosque's interior being cut down to size and about marble columns being taken from the Hippodrome.
In designing the Süleymaniye Mosque, Sinan took inspiration from the Hagia Sophia and the Bayezid II Mosque. Suleiman's intention was to build a mosque that would surpass all others built by his predecessors. Suleiman appears to have represented himself at times as a "second Solomon" and his construction projects in both Jerusalem and Constantinople (Istanbul) appear to reflect this. Architecturally, Suleiman's mausoleum (built behind the mosque) references the Dome of the Rock, which was built on the site of the Temple of Solomon in Jerusalem. According to popular tradition, Justinian I boasted upon the completion of the Hagia Sophia in Constantinople: "Solomon, I have surpassed thee!" Suleiman's mosque, in turn, references the Hagia Sophia in its layout.
Damages and restorations.
The Süleymaniye was damaged in the great fire of 1660 and was restored by Sultan Mehmed IV. Part of the dome collapsed during the earthquake of 1766. Repairs damaged what was left of Sinan's original decoration (recent cleaning has shown that he experimented with blue, before making red the dominant colour of the dome).
During World War I the courtyard was used as a weapons depot, and when some of the ammunition ignited, the mosque suffered another fire. Not until 1956 was it fully restored. The mosque was restored again between 2007 and 2010. Parts of the surrounding complex continued to be restored in the decade following.
Architecture.
Courtyard.
Like the other imperial mosques in Istanbul, the entrance to the mosque is preceded by a forecourt with a central fountain. The main front gate, on the northwest side of the mosque, projects outward from and above the walls on either side. The entrance portal consists of a recess covered by a triangular vault sculpted with "muqarnas", with slender pilasters on either side. Above the "muqarnas" canopy is an inscription featuring the Sunni version of the "shahada" (profession of faith). The windows on either side of the portal mark the presence of interior rooms which housed the "muvakkithane" (chamber of the timekeeper). 
The courtyard, measuring around , is of exceptional grandeur with a colonnaded peristyle supported by tall columns of marble, granite and porphyry. The columns are topped by classic Ottoman "stalactite" capitals (carved with "muqarnas"). On the southeast side of the courtyard, the portico preceding the prayer hall is higher than those on the other three sides, giving this façade a greater monumentality. The three center arches of the northwest portico, corresponding to the front entrance, are also higher than the other arches around them. According to Godfrey Goodwin, reconciling these elements of different heights along the peristyle was Sinan's main aesthetic difficulty. The facade of the prayer hall is also decorated with rectangular Iznik tile window lunettes. It was the first building in which the Iznik tiles included the brightly coloured tomato-red clay under the glaze.
The mosque is equipped with water taps outside the courtyard, between the side entrances of the prayer hall, which are used for performing ablutions. As a result, the drinking fountain in the center of the courtyard is purely decorative. It is a rectangular marble enclosure with a ceiling. The fountain was designed so that water sprayed from the ceiling into the basin below, an unusual feature noted by some 16th-century writers.
Behind the southeast portico, the main entrance to the prayer hall is set within a recess with a complex "muqarnas" canopy. This is preceded by a dome with a more distinctive design than the other domes of the peristyle. The entrance portal features a foundation inscription carved onto three rectangular panels (two vertical panels on the side and an horizontal one on top). The text was composed by Ebussuud Efendi and its calligraphy, in "thuluth" script, was created by Hasan Çelebi, a student of Ahmed Karahisari. It states the sultan's name and titles, his genealogy, and a prayer for the continuation of the Ottoman dynasty. The wooden doors of the entrance are made of carved wood, including walnut, ebony, and olive wood, and they are inlaid with ivory and mother-of-pearl.
The side entrances of the mosque courtyard have inscriptions as well. The western gate to the courtyard has an inscription reading, "Peace be unto thee! Thou art good, so enter ye to dwell therein" (Quran 39:73). The other entrances of the mosque have similar inscriptions which compare its gates with the gates of paradise.
Minarets.
Four minarets occupy the four corners of the courtyard. The two taller ones have three balconies and rise to a high of without their lead caps and including the caps. The balconies are supported by consoles carved with "muqarnas" and they have balustrades carved and pierced with geometric patterns. 
The use of four minarets at the corners of a mosque courtyard had been done previously at the Üç Şerefeli Mosque in Edirne, although Sinan introduced a strict symmetry not present in the earlier example. In the history of Ottoman architecture, this many minarets were only added to some mosques endowed by a sultan (princes and princesses could construct two minarets; others only one). The minarets have a total of ten balconies, which is said to reflect the fact that Suleiman I was the 10th Ottoman sultan. By making the outer minarets shorter than the inner ones, Sinan also increased the overall visual impression of a structure rising towards the central dome.
Prayer hall.
Overall design.
The interior of the mosque is almost a square, measuring , forming a single vast space dominated by its central dome. The dome is high and has a diameter of which is exactly half the height. The square space directly below this dome occupies exactly half the total area of the prayer hall. The layout emulates the dome design of the Hagia Sophia and also follows the layout of the earlier Bayezid II Mosque: the central dome is flanked by semi-domes both in front and behind, covering the main central space, while a row of smaller and lower domes covers each of the two lateral aisles on either side. Between these smaller domes and the main dome are large tympanas filled with windows. This repetition of an older building plan is uncharacteristic of Sinan and may have been the result of Suleiman's personal wishes.
Sinan refined the design by repeating the innovations he had previously used in the Şehzade Mosque. The dome and semi-domes are supported by a limited number of load-bearing pillars and buttresses, allowing for more windows in the walls between them and minimizing any obstructive divisions within the prayer space. He dissimulated many of the load-bearing buttresses by incorporating them into the outer walls, where they project partly inwards and partly outwards so as to make them appear less massive from either side. He built colonnaded galleries between them both on the outside and on the inside, thus further obscuring their presence. Because the supporting buttresses are dissimulated within the walls of the building, they do not dominate and obscure its profile as they do at the Hagia Sophia. Thus, on the outside, the arrangement of arches, turrets, and semi-domes forms a more harmonious, almost pyramid-like progression to the central dome, emphasizing the latter as the visual culmination of the structure. The exception to this is the southeast wall (facing the cemetery), where the buttresses are fully situated on the outside in order to maintain a flat surface for the "qibla" wall on the inside.
Sinan also introduced greater variety and detail to the mosque's design than in previous works. For example, in the domes covering the lateral aisles, he alternated between domes of different sizes, thus introducing a certain visual rhythm. The spaces in front of the side entrances of the prayer hall, between the pairs of massive buttresses at the corners of the building, are also covered by domes of alternating designs: a circular dome in the middle flanked by two smaller elliptical domes on the side. Moreover, by adding these four side entrances at the corners – instead of two side entrances at the middle of the lateral walls, as was done in the Şehzade Mosque – Sinan found a better use for these corner areas that were typically neglected or omitted in other centrally-planned buildings. On the outside, the two level-galleries have wide projecting eaves which shelter water taps used for ablutions, another innovation.
Decoration.
The interior decoration is restrained and this seems to have been deliberate on Sinan's part. The documents of the mosque's "waqf" (religious endowment) explicitly claim that ostentatious ornamentation of gold or jewels was avoided in order to conform with the traditions of the Islamic prophet Muhammad. It's possible that Suleiman and Sinan regarded calligraphy as the primary form of decoration, in the spirit of a period when the Ottoman sultan championed a more austere Sunni orthodoxy. The calligraphy of the mosque is almost entirely in monumental "thuluth" form and is attributed to Hasan Çelebi, whom Sinan may have favoured.
Most or all of the mosque's original painted decoration has been destroyed in the course of later damages and repairs. Very little is known directly about the original painted decoration. The present-day painting of the central dome dates from a 19th-century restoration by the Fossati brothers, who chose to roughly imitate Ottoman Baroque decoration. Traces of the original decoration were found during 20th-century cleaning and suggest that blue colours were used before Sinan replaced them with predominantly red colours. The Fossati-era painting has been maintained in more recent restorations as it is now considered part of the mosque's history. Elsewhere, the voussoirs of the mosque's stone arches are painted in red and white to imitate marble. Except for the inscriptions carved in stone, most of the other calligraphy found throughout the mosque is painted and was thus likely restored in later periods. The restorations appear to have been careful and probably retain some aspects of the original compositions.
The stonework of the mosque is of high quality. The columns have classic Ottoman "stalactite" or "muqarnas"-carved capitals. On both the front and back sides of the four main pillars are