Every day, thousands of people drive under the Bozdoğan Arch, spend their weekends in touch with nature in the Belgrad Forest, meet in Taksim Square, and often do not notice the spirit level or historical fountains on the wall of the Şehzade Mosque.
However, most of Istanbul's most well-known points form parts of a giant engineering network that has formed interconnected rings of the same water system for centuries.
The dams, aqueducts, galleries, mazes and fountains that stand as cultural heritage today bear the traces of the invisible water civilization that extends from Rome to Byzantium, from the Ottoman Empire to the present day and made the growth of Istanbul possible.
Traces of Istanbul's relationship with water date back approximately 19 centuries. The city's first documented water facilities were built during the reign of Roman Emperor Hadrian (117-138 AD).
In order to meet the growing water needs with the increase in population, water taken from sources outside the city was delivered to residential areas through canals and waterways.
By the 4th century, Istanbul's need for water increased with its growing population. During the reign of Emperor Valens, water was transported to the city from distant sources through the transmission lines of which the Valens Aqueduct, known today as the Bozdoğan Aqueduct, is a part, and Istanbul gained new water resources.
The infrastructure established during the Roman and Byzantine periods was kept alive after the conquest of Istanbul, when Fatih Sultan Mehmet repaired the dilapidated waterways and made them functional again.
With the Kırkçeşme Water System built by Mimar Sinan during the reign of Suleiman the Magnificent, Istanbul gained one of the most advanced water infrastructures of its age.
With its approximately 55 kilometers of transmission lines, 33 aqueducts, kilometers-long galleries, control chimneys, spirit levels, machines and distribution structures, the system is considered one of the largest engineering projects not only of the Ottoman Empire, but also of the 16th century.
AA team traced the historical water system step by step
The kilometer-long journey of every drop of water accumulated in the Belgrade Forest reveals not only an engineering achievement, but also a city memory stretching from Rome to Byzantium, from the Ottoman Empire to the Republic.
Anadolu Agency traced this story, which millions of Istanbulites live in unknowingly today, by following the historical water system step by step.
The journey of water across Istanbul began at the dams in the Belgrade Forest. Rain and spring waters accumulated in the Valide, Topuzlu, Kirazlı and Sultan Mahmud dams deep within the forest, known today for its hiking trails and natural beauties, fed the historical water system throughout the year.
The waters, which separated from the dams and proceeded from two main branches, east and west, merged in the Başhavuz, at a depth of approximately 14 meters, in the south of Kemerburgaz. The water, which was rested here for a while and cleared of its sediments, was then transferred to the main transmission line extending towards Istanbul.
Known by very few people today and described by Mimar Sinan as "as deep as the Galata Tower", Başhavuz was one of the most critical stops of the system where water from different sources collected at a single point and continued their journey towards the city.
The water given from the head pool to the main transmission line passed through Mağlova Aqueduct, one of the most important examples of Mimar Sinan's mastery in water engineering, and reached Istanbul via Uzunkemer, Güzelcekemer and Paşakemeri.
Mağlova Aqueduct, which is approximately 36 meters high and has a two-storey carrier system, allows water to be transported from one side of the valley to the other, and with its unique architecture and engineering features, it is among the important works of not only Ottoman water architecture but also the world water engineering history.
When the water reached the center of the city, it passed through the Bozdoğan Aqueduct, which has been a part of Istanbul's skyline for approximately 16 centuries. The aqueduct, which was completed in 378 AD during the reign of Roman Emperor Valens and was repaired many times during the Ottoman period and continued to be used as a part of the water system, played an important role in transporting water from distant sources to the historical peninsula.
Maksem, which gave its name to Taksim
One of the important stops of the water's journey within the city was Taksim Maksemi. The water delivered to the city was divided into branches here and directed to fountains and other distribution points, and this structure, where water was "divided" into different lines, gave the region where it is located today its name, Taksim.
In the meantime, the systems that meet Istanbul's water needs have changed; modern dams, treatment facilities and new transmission lines have been established.
Historical dams, arches and maksems have largely completed their initial functions and become part of the cultural heritage. However, some dams continue to contribute to the water system today.
According to experts, it is not just the individual monuments that need to be protected, but the holistic water network connecting these structures and the story of civilization it tells.
In this context, it is recommended that the Kırkçeşme Water System, which starts from the Belgrad Forest and extends to the city center through historical arches, be considered as a cultural route and the historical fountains that gave its name to the Kırkçeşme Water Facilities, which were removed during road works in the 1940s, be revived.
Istanbul's water story began in the Roman period
Istanbul Medeniyet University, Faculty of Letters, Department of Art History, Lecturer Prof. Dr. Kadir Pektaş, in his statement to the AA correspondent, said that water has played a decisive role in the establishment of large cities throughout history, and that Istanbul has a large infrastructure that has been constantly developed by different civilizations to meet its water needs for centuries.
Explaining that the origins of Istanbul's historical water system date back to the Roman period, Pektaş stated that different civilizations from the Byzantine to the Ottoman developed and used the same infrastructure.
Stating that the first documented water facilities in the city were built during the reign of Roman Emperor Hadrian, Pektaş said, "It is known that water was brought to Istanbul via Istrancalar and Çatalca during the reign of Constantine the Great. Water transportation from the Belgrade Forest to the city dates back to the 4th century. The Valens Aqueduct, that is, the Bozdoğan Aqueduct, located right behind us, is one of the important parts of this large water system." he said.
The Ottoman Empire continued and developed the existing system
Stating that the Ottoman Empire preserved and developed the water infrastructure inherited from Rome and Byzantium after conquering Istanbul, Pektaş said, "After the conquest of Istanbul, Fatih Sultan Mehmet made the dilapidated waterways functional again. According to the information provided by historian Tursun Bey, especially the waterways and aqueducts coming from Halkalı were repaired and new ones were built. These works did not only remain in the period of Mehmet the Conqueror, but the next sultans also improved the system by adding new structures to the water facilities. continued." he said.
Stating that the largest water system in Istanbul is the Kırkçeşme Water Facilities built by Mimar Sinan, Pektaş emphasized that the facilities are a very large system that brings water to Istanbul from the Belgrade Forest, which is approximately 55 kilometers away.
Pektaş said, "Actually, there were water facilities in the region from the Roman and Eastern Roman periods, but these were destroyed over time. The Ottomans reconsidered this infrastructure, especially in the 16th century, and established a much more advanced system under the leadership of Mimar Sinan. The name Kırkçeşme comes from the many fountains located near the Bozdoğan Aqueduct and which no longer exist today." he said.
Water was delivered to Istanbul from two main branches.
Explaining that the system does not consist of just a few arches, but a large interconnected engineering network, Pektaş said that water is delivered to Istanbul through two separate routes, starting from the Belgrad Forest.
Prof. Dr. Pektaş explained that the waters coming from Kirazlı, Topuzlu and Paşa streams are collected in the eastern branch, and the waters coming from Ayvat, Orta and Bakraç streams in the western branch are included in the system.
Pektaş said, "These two main lines meet in the large pool in the south of Kemerburgaz, and the water stagnated here was then passed through the Mağlova Aqueduct and reached Eğrikapı and Taksim Maksemi via Güzelcekemer, and was then distributed to the neighborhoods and fountains through pipes and spirit levels." he said.
Istanbul's largest water project was implemented by the order of Suleiman the Magnificent.
Stating that the facilities were built by the order of Suleiman the Magnificent in order to meet the increasing water needs of Istanbul, Pektaş also explained the remarkable statements in historical sources regarding the emergence of the project as follows:
"During a hunt, Suleiman the Magnificent noticed the water resources around Kağıthane and the Belgrade Forest. When Istanbul's need for water gradually increased, he ordered Mimar Sinan to do research to bring these waters to the city. The project prepared by Sinan was presented to the sultan and it was decided to implement it despite its high cost. According to the rumor conveyed by Evliya Çelebi, Mimar Sinan said that the cost of lining up coin purses from the Belgrade Forest to Istanbul would be as great as lining them up end to end. Suleiman the Magnificent says, 'We line up the coin purses not end to end, but even side by side, as long as you bring the water.' He supports the project by saying "
Explaining that the system does not only consist of dams and arches, but also a very detailed planned engineering network, Pektaş said that the waters coming from the east and west are collected in the large pool near Kemerburgaz.
Pektaş said, "This pool, which is approximately 14 meters deep, was, in the words of Mimar Sinan, a structure as deep as the Galata Tower. Water coming from the east and west was rested here and then given to the main transmission line. Although it is not well known today because it is outside the city center, in my opinion, it is one of the structures whose rights have been violated the most." he said.
Up to 30 thousand cubic meters of water were supplied to Istanbul
Pektaş explained that the system works with a complex engineering network, including galleries, control chimneys and intermediate water sources, and said:
"Water was moving through galleries. When sloping valleys were encountered along the line, arches were built. It is known that there were approximately 33 arches in Kırkçeşme Water Facilities. Control chimneys were left on the galleries at intervals of 20 to 40 meters. In addition, when a new water source was detected on the route, these sources were included in the system. With the system established by Mimar Sinan, approximately 17 thousand 500 cubic meters of water were delivered to Istanbul daily, and with subsequent additions, this amount increased to 30 thousand." It is estimated that it is up to cubic metres."
Mağlova Aqueduct is one of the masterpieces of world water engineering
Pointing out that the Mağlova Arch is one of the most important works that show that Mimar Sinan was not only a great architect but also a superior engineer, Pektaş emphasized that the structure is a unique example of engineering on a world scale.
Pektaş said, "The Mağlova Aqueduct, which is approximately 36 meters high and 250 meters long, is one of the most important works of not only the Ottoman but also the world's water architecture, with its two-storey structure and carrier system. I always make this analogy; the Mağlova Aqueduct is for water architecture what the Selimiye Mosque is for centrally planned mosques. In my opinion, the Ottoman Empire has gone beyond the level reached by Rome in water engineering." he said.
Stating that Kırkçeşme Water Facilities faced a major natural disaster after its construction, Pektaş said, "Despite the centuries that have passed, a significant part of the dams and structures are still standing today. Some dams even continue to function today. This shows how accurate the investments were, and also shows that the structures were built strong enough to survive for centuries." he said.
Spirit levels maintained not only the pressure but also the quality of the water
Prof. stated that water in the system is not carried only by arches. Dr. Pektaş said that water is distributed to the city in a controlled manner, thanks to underground pipes, spirit levels and scales.
Pektaş said, "Part of the water brought to Istanbul through aqueducts continued on its way through underground pipes. Spirit levels were placed at the points deemed necessary on the line. Spirit levels, which can still be seen on the outer wall of the Şehzade Mosque today, prevented the water coming with high flow rate from damaging the pipes and balanced the pressure. At the same time, they raised the water to the upper level, allowing it to come into contact with the air and contributing to the preservation of the quality of the water." he said.
Explaining that the water passing through the spirit scales reaches the maximum, Pektaş stated that these structures are one of the most critical points in Istanbul's water distribution system and continued as follows:
"The water then reached the neighborhood maksems, and from there it was distributed to the square fountains, streets and neighborhoods through underground lines. One of the most important distribution points of Kırkçeşme Water Facilities was Eğrikapı Maksemi. The octagonal maksem, which gave its name to the Taksim district today, is one of the important parts of this system. In the lower part of this structure, which was completed during the reign of Mahmut I, water was shared among the neighborhoods and fountains, that is, 'divided'. Kırkçeşme Water "It is known that after the construction of the Facilities, the system delivered water to more than 30 fountains. This was a very large capacity for the 16th century."
"The invisible backbone of Istanbul"
Stating that millions of people in Istanbul pass by historical water structures every day, but it is not known enough that they are parts of the same system, Pektaş said that historical waterways should be considered as the "invisible backbone" of the city.
Pektaş said, "Today, people come to Belgrade Forest to walk, ride a bike or have a picnic. Some of them know what these structures are, but a significant part of them is not aware that they are parts of a large system that has met the water needs of Istanbul for centuries. It will be important to prepare promotional signs explaining the function and history of these structures. Especially the spirit levels and maqsems located in the streets are often mistaken for tombs or different structures. However, explaining what they are will contribute to increasing awareness about the historical water system." he said.
Cultural route proposal for Kırkçeşme Water Facilities
Stating that Istanbul's historical water system can also be used in cultural tourism, Pektaş suggested creating a special tourist route for the historical water line starting from the Belgrad Forest and extending to Kağıthane Valley.
Pektaş said, "Special touristic routes describing only Kırkçeşme Water Facilities can be created on the route starting from Belgrade Forest and extending to Kağıthane Valley. Dams, arches, galleries and other water structures can be explained to visitors in a single route. I think it would be a very valuable cultural route for Istanbul." he said.
Emphasizing that historical waterways are not independent structures from each other, Pektaş stated that the development of Istanbul can be read through the water system and said, "It is of great importance to protect and preserve these structures, which form the entire backbone of Istanbul with main lines, side lines, weirs and distribution points, with a holistic approach." He concluded his words by saying.
