It's a given that any tourist visiting İstanbul will, along with trips to Topkapı Palace, the Blue Mosque and probably the Grand Bazaar, make the pilgrimage to Aya Sofya (also known as Hagia Sophia or “Church of the Holy Wisdom”). But what is it that makes this near 15-century-old building, which rises imposingly from the heart of the city's historic Sultanahmet district, so special?
So important that in 1985 Aya Sofya (Hagia Sophia) was chosen as a World Heritage site by UNESCO, so beguiling that in 2010 it attracted some two-and-a-half million visitors, despite the rather hefty admission fee.
The origins of a masterpiece
The building you see today, less the many accretions that have been added over the centuries, dates back to A.D. 537 when, after a five-year building program, Hagia Sophia was finally dedicated by one of the Byzantine Empire's most powerful and successful rulers, Justinian. It wasn't the first church to stand on this site, though. The original, inaugurated in A.D. 360, was burnt in a riot in 404. Its replacement suffered a similar fate in the infamous Nika Revolt of 532, a cataclysmic event that almost led to the overthrow of Justinian, but ended instead with the massacre of some 30,000 rioters in the chariot racing stadium, the Hippodrome (today's newly repaved and spruced up At Meydanı, adjacent to the Blue Mosque). Visitors today can still see the remnants of the church's second incarnation, with great slabs of elaborately relief-carved marble lying outside the monumental western entrance to Justinian's replacement, and the stepped base of the structure visible in a large excavated trench just to the left of the main portal.
The Emperor Justinian used the devastation wrought by the Nika rioters to his own advantage, as building a new and much grander church on the site would both glorify God and, as a Byzantine emperor was God's representative on Earth, help cement his position as both temporal and spiritual ruler of the empire. Justinian was determined to use the best materials, the best craftsmen and, of course, the very best architects to achieve his goal, and appointed mathematician and physicist Anthemius of Tralles (modern Aydın) and an expert in geometry, Isidorus of Miletus (today a well-known Greco-Roman site on the Aegean coast close to Kusadası) to design and oversee the whole building process.
It’s a dome thing
Domes were nothing new in the sixth century. Rome's Pantheon, with its innovative concrete dome, preceded Aya Sofya by over four centuries. Closer to home, a temple at the fascinating Asclepium (ancient healing center) at Pergamon on Turkey's Aegean coast, was a half-size replica of the Pantheon (unfortunately, today only a couple of courses of masonry mark-out the ground-plan of the original structure). Nonetheless, and despite some experimentation, prior to the construction of Aya Sofya, most churches had been based on the rectangular style of the Roman meeting hall or basilica and had pitched roofs.
The brilliance of Anthemius and Isodorus was to take the existing model of the basilica church but surmount the basic structure with an enormous dome, some 32 meters in diameter, with the top of the dome an incredible 55 meters above the floor. The real genius, however, came with the addition of two half domes, one to the east above the apse, the other to the west above the main entranceway. In doing this, the architects achieved the incredible sense of space inside Aya Sofya, with one's eyes drawn irresistibly upwards to, as the architects envisaged, a hovering space representing heaven itself, all coated with glimmering gold mosaic and lit by the 40 windows piercing the base of the central dome.
Engineering and other matters
The engineering behind the structure is mightily impressive. Just take a walk around one of the four massive piers that take the bulk of the weight of the dome to realize just how substantial they are, bearing in mind that each pier is held in place by a monumental buttress. The design was far from flawless, however, perhaps not surprisingly given the boldness and innovative nature of the design. Twenty-one years after its dedication parts of the dome collapsed after an earthquake and the son of Isodorus of Miletos, as able as his father, was called in to make repairs. His solution was to raise the height and steepness of the dome, thus making it more stable.
Aya Sofya impresses today by its sheer size, but imagine how it must have struck the man in the street at the time of Justinian, when it would have dwarfed most other buildings, and when the great imperial mosques of the Ottoman İstanbul that draw the eye of today's visitor were still nearly a thousand years away. Although nothing quite as ambitious as Hagia Sophia was attempted again, it did set the pattern for the domed churches that predominated throughout the Byzantine world, and of course it was the inspiration for the Ottoman mosques that followed.
The exterior of the church is a disappointment to some visitors who often compare it unfavorably to the cleaner, more coherent lines of the nearby Blue Mosque. This is, of course, largely due to the many buttresses that have been added over the centuries to support the earthquake-wracked edifice (though even some of these, notably those added by that brilliant doyen of Ottoman architects, Sinan, are works of art in their own right). It's also worth stating the obvious that the architects original conception did not involve the four minarets (one of which was designed by, you guessed it, Sinan) that today stand sentinel at each corner of the building, nor the assorted tombs of Ottoman sultans later built alongside it.
Inside the masterpiece
Few visitors are, however, disappointed with the magnificent interior of this former church, as apart from the moving sense of space created by the domes, there's always something to catch the eye. The experts are not entirely sure whether the cathedral would have included any figural mosaics in its original conception, but if there were any they were destroyed in the great “graven images” iconoclastic period (roughly 730-843), so the mosaics today's visitor admires post-date this tumultuous period. The figural mosaic most revered by experts is that of John the Baptist and the Virgin Mary beseeching an impassive looking Christ to save mankind on the Last Judgment Day. Situated on a wall of the south gallery, it's a moving work of art. To really admire the workmanship involved, take a pair of binoculars along as a guard rail keeps visitors well-back. Binoculars are also invaluable in viewing the mosaic of the Virgin Mary and infant Christ in the apse.
Other mosaics give us some idea of what some of Byzantine rulers looked like. See Leo VI prostrated in front of an enthroned Christ above the main door between the inner narthex and nave, seeking forgiveness for marrying a fourth time when Orthodox rules permit only three marriages, or the Virgin Mary and infant Christ flanked by Justinian and Constantine, the former offering the pair a model of Hagia Sophia, the latter a model of the walled city of Constantinople. There's much else to be seen, from the Viking graffiti on the south gallery rail to the superbly carved capitals bearing the monograms of the Emperor Justinian and his wife, Theodora, and from the purplish Egyptian porphyry columns to the empty (his bones were supposedly thrown to the street dogs after the Byzantines recaptured Constantinople in 1261) tomb of the Doge of Venice, Dandalo, who treacherously aided the Crusaders in the capture of Constantinople in 1204.
The spiritual center of two empires
When Sultan Mehmet the Conqueror entered the Church of the Holy Wisdom on May 29, 1453, a new chapter was about to open in the history of one of the world's great buildings. For nearly a thousand years Hagia Sophia had been the religious heart of one of the world's greatest (if often maligned) empires, that of Byzantium. Sultan Mehmet II, who saw himself as the natural and rightful heir to Byzantium, immediately decided that is should serve as a mosque. And, despite the fact that many other imperial mosques were built during the Ottoman centuries, Aya Sofya Camii, as Hagia Sophia was now known, remained the most important in the city, just a stone's throw from the sultan's residence and political nerve-center of the empire, Topkapı Palace. And just as Byzantine rulers had been crowned in full pomp and splendor in the cathedral, so new Ottoman sultans would first reveal themselves to their subjects at Friday prayers. The cathedral turned mosque naturally accrued a prayer niche (mihrab) facing Mecca, slightly offset in the apse, a mimbar replaced the Byzantine ambo, or pulpit, along with prayer platforms (hunkar mahfil), medallions (levha) inscribed with the names of Allah, the Prophet, and the first caliphs and imams. The building thus remained a place of worship and official ceremony, at the heart of an empire even greater than that of Byzantium. Architecturally innovative, superbly situated on İstanbul's first hill, beautifully decorated and a spiritual home to two great faiths, Aya Sofya, since the 1930s a museum, is one of the world's great buildings.
Aya Sofya Museum: Open daily except Monday. Summer opens at 9 a.m., last entry 6 p.m., closes at 7 p.m. Optional audio sets TL 10, admission TL 20.