Historical Development of Hagia Sophia

The name of Hagia Sophia is originated from Greek, which stands for “The Church Of Holy Wisdom”. In Latin, it is named as Sancta Sophia and finally in Turkish, as Ayasofya. Hagia Sophia has always been regarded to be one of the most prodigious architectural wonders, having an important role in history with its construction, architectural techniques utilized, its size and function. It was the biggest church constructed by the Eastern Roman Empire in Istanbul (earlier Constantinople) and for many years, the biggest mosque in the Islamic world. Today, Hagia Sophia is still standing today with a charm and glory. The exterior and interior view of the Hagia Sophia is presented in Figure-1 and Figure-2 respectively.

Based on the archival records for the Mehmet-II period, Hagia Sophia is constructed on a land that belonged to the Fatih Sultan Mehmed Han Foundation. The land was utilized for maoseleum, akaret, muvakkithane and madrasah on 57 pafta, 57 island and 7th parcel. It is situated nearly 115 m away from the Basilica Cistern (YerabatanSarnıcı), 370 m from the Blue Mosque (Sultanahmet Camii) and 430 m from the Topkapi Palace, which are all situated in the historical peninsula of Istanbul (Özçelik, 2015).

Throughout history, Hagia Sophia has been constructed on the same spot for three times. It was the imperial cathedral for 916 years. Throughout the course of history, Hagia Sofia has been transformed into a mosque and served 481 years to the Ottomans and since 1934 it has served as a museum (Hagia Sophia Museum, 2018).

In this study, we investigated the architectural characteristics of Hagia Sophia. Also, we emphasize the geometrical structure and its influence on the interior light reflection. Firstly, a brief history is given from the architectural perspective. Secondly, construction and design characteristics are explained, detailing within the dome, the apse, the geometry and light effects. Thirdly, additions made for the conversion to a mosque is presented.

1. Brief History

Although rare, historical references illustrate that Hagia Sophia has been constructed on three occasions throughout the previous history. The bricks that are collected from various excavations are branded as Megale Ekklesia (Big Church), which reveals the name of the first church. It was constructed by Emperor Constantius (337-361) in 360 A.D. The roof was composed out of wood and was made to extend vertically (basilica) which suffered damages and was ultimately destroyed after a public riot in 404 A.D. The sole and most prominent remain from the first church is the Patriarch Ioannes Chrysostomos’s mosaic portrait that can still be viewed at the tympanum wall located at the northern part of the church (Hagia Sophia Museum, 2018).

The second church had also a wooden roof, which was rebuilt by Emperor Theodosius II (408-450) in 415. It had also a basilical structure and contained five naves with a monumental door (Propylon). The church was demolished in 532, again after a public riot during Emperor Justinianos’ reign (527-565). The remains, which can be seen near the west entrance that stay two meter below the ground, are from the second church. As has been shown in Figure-3, there are some column bases and lamb embossing pieces that represent the 12 apostles (Özçelik, 2015).

The third (and the last) church was built by architects, Isidoros of Milet and Anthemius of Tralles. The construction started during the reign of Emperor Justinian (527-565) on February 23, 532 A.D. It is finished within a very short period of time of five years. It was opened by Emperor Justinian with a ceremony on December 27, 537 A.D. It is said that, during the ceremony, Emperor Justinian entered the temple and said, “My Lord, thank you for giving me chance to create such a worshipping place. Suleiman, I beat you,” referring to the Suleiman’s temple in Jerusalem.

For nearly a millennium, the Hagia Sophia was the imperial cathedral for the East Roman Empire. The emperors were crowned at the very spot on the east side of the naos. The intertwining omphalion design of the spot is upholstered and decorated with various coloured marbles. Unfortunately, the church was badly vandalized by the Latins during the invasions between 1204 and 1261. It was until when the Romans recovered the city, did they make the necessary repairs.

Eventually, after the Ottomans conquered Istanbul, which is regarded to be the end of the Eastern Roman empire, Hagia Sophia is named as Ayasofya and transformed into a mosque. Fatih Sultan Mehmet and his predecessors kept the main plan as it is. However, some additions have been made to convert it into a mosque, along with the necessary fortifications. For nearly 15 centuries, some pillars have been installed and buttresses have been added. In addition to this, after 1453A.D, four minarets (by Mimar Sinan), a madrasa, a şadırvan (fountain), various Sultan tombs etc. are constructed at the exterior of the main structure (Özçelik, 2015).

With the Turkish Republic Revolution in 1923, the Hagia Sophia was converted into a museum by the great leader Mustafa Kemal Atatürk and since February 1, 1935 A.D, it has been welcoming tourists all over the world.

2. Construction and Architectural Design

The third Hagia Sophia construction process is one of the earliest examples of early Byzantine architecture. It has a basilica to accommodate the architectural plan to include a huge dome, which is augmented with two half-domes. The second floor could be accessed by a staircase, which has been constructed as a ramp, where flat stones are upholstered on the ramp floor. A section of the Hagia Sophia is presented in Figure-4.

As like most of the other big cathedrals in Europe, there are two nartexes in Hagia Sophia. The nartex serves as a transition from everyday life to the divine and preparation for the worship. The interior nartex is shown in Figure-5 and the exterior nartex is shown in Figure-6 respectively. The width of the exterior nartex is 69.5 m and from the apse to the exterior nartex, the length is 100 m.

Specifically the church has a square design. It can be easily seen that on the ceiling section, a dome (circle) sits on a square pattern. The square symbolizes the life and the circle symbolizes the heaven. The size of the square is 100 Byzantine feet and the dome is emplaced in within square mainly with the utilization of the pendentives and the dome is buttressed with two half-domes (Jabi and Potamianos, 2007).

The aforementioned sizes have been impressive, considering the periods that the church was build. The construction technique and architectural design had been so prodigious that the Hagia Sophia had been a benchmark monument for many centuries. In addition to this, the combination of the basillical plan, the dome and two half-domes, arches, pendentives and vaults give rise to a very spacious interior as well as a wide worshipping area (Sqour, 2016).

2.1 Structural Elements

In total, there are 104 columns in Hagia Sophia. 40 of them are in the lower gallery and 64 of them are on the upper gallery. The detail of four of the columns on the lower gallery can be seen in Figure-6. The columns are collected from the ancient ruins of era of different Roman emperors, such as the Ephesus, Aspendus, Tarsa and Baalbeek. Apparently, the structure is upholstered and designed with various different kinds of marbles where the pink marbles are collected from Afyonkarahisar, white ones are from the Marmara Island, the yellow ones from North Africa and the green porphyry from Eğriboz Island. In addition, the naves include spectacularly large columns, which are taken from the Temple of Artemis and Egypt to support the dome and half-domes (Live Science, 2013).

The usage of pendentives which transform a square into a circle is illustrated in Figure-7. They are used to transfer the loads from the dome, down to the base walls and finally onto the ground. This kind of utilization of pendentives and turning a square structure to a circular shape is regarded to be a distinctive feature of the Byzantine architecture style. All the pendentives have been fortified and reinforced in time, with 24 buttresses (Özçelik, 2015).

2.2 The Dome and the Apse

A Dome is a projected circular architectural element used to cover the ceilings of buildings. The first examples of dome structure can be seen in Mesopotamia, beginning in the 4th millennium BC. The techniques and design of dome building are further developed and enriched by Romans and Byzantines. In addition to this, the usage of a dome necessitates the utilization of additional supporting structures to pass the heavy load to the ground. Examples of such structures are the pendentives, columns, arches etc. (Sqour, 2016).

The height of the Hagia Sophia dome from the ground level is nearly 56 m with and the radius of 31.9 m in the North to South direction and 30.9 in the East to West direction. The construction was performed through the utilisation brick and mortar as the main materials for the dome (Live Science, 2013).

It is believed that the dome of Hagia Sophia has inspired the style and technique of temple architecture. Actually, the Romans utilized the domes to transform a square plan into a circular plan. Specifically, for the purpose of using both square and circle at once, they used to pursue the Persian technique which can be seen on fire worshipping temples. In addition, Ottomans used the dome architecture on all of the big sized mosques and the technique is still valid today (Sqour, 2016).

The apse was designed as a circle which has been placed at the junction of the longitudinal axis of the Church with the interior side of the eastern wall of the main building, as has been shown in Figure-8.There is a spectacular mosaic of baby Jesus Crist sitting on Virgin Mary’s lap. In Hagia Sophia, the apse is semi-circular on the inside and three-sided on the outside of the structure. The axis of the church is precisely aligned with the third hour of the equinox with an azimuth angle of 123.4° where the alignments of azimuth angles of the Sun take place with the altar on the particular dates and hours of the year of its design (JabiandPotamianos, 2007).

2.4 Decoration, Embossing and Mosaics

On Hagia Sophia walls, there are exceptionally fantastic mosaics and decoration examples, which are decorated on the walls, apse, nartex and upper gallery. The walls are covered with marble or they are left blank. However, most of the marbles are cut vertically to achieve a symmetrical pattern, which reflect a veiny look on the walls. While the mosaics which are designed with plant and flower shapes date back to the Sixth century, the figured ones are from the Iconoclast period. The mosaic on the apse wall, the angel figures on the pendentives, the mosaic of Saint Ioannes Khrisostomos, Saint Theophoros İgnatios and Saint Athanasios are such exuberant examples (Erdehan, 2010).

After conversion to a mosque, most of the mosaics are covered but the one on the apse and the ones on the upper gallery are kept as they are. Eight calligraphic panels which read Allah, Hz. Muhammed, Hz. Ebubekir, Hz. Ömer, Hz. Osman, Hz. Ali, Hz. Hasanve Hz. Hüseyin are written by Caligrapher Kadıasker Mustafa İzzet Efendi. They are the widest caligraps known throughout the Islamic world with a diameter of 7.5 m.

There are two bronze şamdans (lamps) on both side of the mihrab, which were gifts to Kanuni Sultan Süleyman (1520-1566) on his return from Budin. Also, there are two marble cubes, just next to the main entrance, which are from the third century of Hellenistic period BC. It is believed that they originated from Bergama and were presented as gifts toSultan Murad III (1574-1595) (Hagia Sophia Museum, 2018).

3. Geometry and Light Reflection

The geometry of Hagia Sophia is based on a Greek cross layout, inscribed in a square box. The area in the center of this cross is the room of the square base that supports the dome. This base is not actually perfectly straight; it curves into the dome, helping to support it while also allowing the weight to flow downwards and cause less tension on the structure (Live Science, 2013).

The light, ambiance and reflection of the interior of Hagia Sophia is so fantastic that the windows, which, pass the sunlight are perfectly aligned to the position of the Sun. Specifically, the windows on the apse are significant as on Christian celebration days, they admit a light shaft on the altar. Also, it resembles the descent of the Holy Spirit and correlates with mosaic on the Apse (Jabi and Potamianos, 2007).

The dome and the pendentives are lighted up with 40 arched windows and the two half-domes which are placed on the west and east sides of the dome have 5 windowed arrays. However, the biggest light source of the church is the two huge windows which are placed on the western corner of the naves. Although, all the windows serve as direct and constant sources sunlight, it is believed that the windows were once covered with colorful tiles reflecting the interior of the church as a divine worshipping place (Jabi and Potamianos, 2007).

4. Conversion to a Mosque

When a new city is conquered, it was a general custom for the Ottomans to convert the biggest church in the city, to a mosque. Thus Hagia Sophia was swiftly converted to a mosque right after Fatih Sultan Mehmet entered the city in 1453A.D. Although the structure was well-fitted to be a mosque, the interior needed some transformation. Firstly, the visual distractions for the prayer, such as the mosaics and iconostasis were covered with gypsum plaster. A temporary mihrab and a minbaris were placed facing to the Kıble direction which is the direction to the holy city of Mekke.

In time, there have been numerous structural additions, however, the architecture is conserved its origin. The most eminent architectural additions are the four minarets. Three of them are constructed by stone and the one on the North West wing, which is believed to be constructed by Fatih Sultan Mehmet, is made of bricks. The two minarets on the west wing are identical, which becomes sharper after the şerefes, which are the rounded balconies on the minarets (Özçelik, 2016).

In 1572 A.D, Selim II ordered to erect another minaret. However, the addition necessitated serious extensions of the buttresses, which are shown in Figure-9. Hence, Mimar Sinan demolished the south west minaret and erected two identical imarets to the west wing. During the 16th and 17th Century Ottoman period, mihrabs, minbar, maksoorahs, a preachment stand and a muezzin mahfili (a special raised platform in a mosque, opposite the minbar where a muezzin kneels and chants in response to the imam’s prayers) were added to the structure. In addition to this, it has been revealed with the excavation that took place in 1982 A.D that a madrasah was built next to the north of the structure during the reign of Mehmet-II and was rebuilt by Sultan Aldulmecit between 1839 and 1861 A.D (Hagia SophiaMuseum, 2018).

REFERENCES

Jabi, W., and Potamianos, I., (2007).Geometry, Light, and Cosmology in the Church of Hagia Sophia.Multimodal Mixed Reality Interfaces for Visualizing Digital Heritage, 2(5), 305-321.

Özçelik, A. C. (2015). Ayasofya’nınMimariÖzellikleriveSüslemeleri. SelçukÜniversitesiEdebiyatFakültesiSanatTarihiBölümü, YüksekLisansTezi.

Sqour, S., (2016).Influence of Hagia Sophia on the Construction of Dome in Mosque Architecture.8th International Conference on Latest Trends in Engineering and Technology (ICLTET'2016). pp.: 5-12.