The city of Gaziantep is located on the edge of the Alleben Stream and the settlement history of the city dates to end of the 5th century. The stream flows by winding the settlement area in C shape. However, Alleben Stream is low in water and the water level is further reduced by increasing summer temperature. The Gaziantep Plateau also has a small number of streams. Moreover, the geological structure of the Gaziantep Region does not allow for lake formation. Depending on the geological structure, a large part of the rainfall seeps underground and forms underground waters. For all these reasons, the settlement has required water transport. In the province of Gaziantep, summers are warm and hot. If water is transported by surface water, it will evaporate in a considerable amount, especially in summer. At this point, the formation of soft limestone, clayey limestone and chalk formation that the city situated on made it possible to excavate the water tunnels underground, and thanks to the tunnel opening to the main rock, the water is moved to the settlement from the source.
The historical water system of Gaziantep consists of underground water tunnels (livas in local language) that bring water to the city from the main source far from the settlement area and the water structures (kastel in local language) that open the water coming from these tunnels for use.
Livas’ are underground water tunnels created with human labor by digging the limestone rock block that the city was built on. The essence of the livas system is based on the principle of bringing water from a source outside the settlement to the center of the city with underground water tunnels, delivering it to large settlements through well-calculated gently sloping underground tunnels and distributing it to water structures at the required places. As the city grew, the underground water network was enlarged by opening the new tunnels in the same way. This has created the ‘system of livas’ that surrounds the underground of the city as a cobweb and continues for miles.
The oldest livas line carrying water to the old city center is the Pancarlı Livas Line which carries water to the city from about 14 km northwest of the city. The period of construction and the origin of the system have yet to be ascertained, however it is clear that the system has been added to over time in parallel with the growth of the settlement. It is understood from the registry records of the Ottoman era that this line proved to be an important water line providing water for many monumental structures in the city, such as khans, madrasahs, baths, mosques, fountains and private houses by way of wells. The livas' also provided water to special structures for the public usage of water, referred to locally as kastels.
Kastels are structures where water from the livas’ is opened for public use. Depending on the elevation of livas, kastels are located at varying depths based on the level of the livas lines. Instead of taking the water up with an additional system, the constructions were built at the water level. Some of the kastels reaching to the present day are "completely below- ground kastels" while some of them are "partly below-ground kastels". Kastels are quite comprehensively planned structures for that they include spatial arrangements for many different functions, serving as pools, wells, sitting places, small mosques, water closets and places for bathing. With these functions, kastels, together with the water-related service areas, has become an important meeting place in the daily social life of the city where people come together, spend time, do their work and perform their religious worship. They were also used to cool off during hot summer days. With the possibilities provided by these structures, they have brought along an important municipal social service.
There is a livas system that provides clean water for every kastel structure while the sewage is moved from the structures by another system. Along with having many livas network underground, some kastels get water from the same livas line. In addition, the following spaces are common in many kastels structures; pool, shower, toilet, mosque. Although we know to be more in quantity, six have reached to the present day:
The Kastel of Pişirici (Beşinci): It is thought to have been constructed during the period of Mameluke, in the years of 1282-83. It is estimated that it is the oldest of the existing kastels in Gaziantep and it has the most developed plane scheme, with two connected spaces. Going down the stairs from ground level, the first space encountered houses pools, places to sit, WC and bathing pool, while the second space, which is divided from the first space with two steps, is functioned as a small mosque. Maintenance and repair work has been completed and it is open to public visit today.
The Kastel of İhsan Bey (Esenbek) Kastel: İhsan Bey (Esenbek) Kastel, which is located under the courtyard of the mosque, is one of those that are "completely below- ground kastels". It is dated to the 15th century. While it is a rock-carved place, the spatial separation is made with masonry walls. The kastel in the present day includes a pool, places to sit and a small mosque, although earlier records indicate a number of changes and additions that have been made over time. Accordingly, it is apparent that WCs existed in the kastel. The cleaning work is completed and it serves as a museum today.
The Kastel of Şeyh Fethullah: It is located in the courtyard of Şeyh Fethullah Mosque., and was a part of the mosque complex, together with hamam, madrasa and zawiyah during the era. Currently, half of the kastel is above ground, although some parts have no upper structure. Documentation held by the Wakf of Şeyh Fethullah Efendi notes the existence of a U-shaped madrasah in the courtyard of the Mosque, and it is likely that the Kastel of Şeyh Fethullah was constructed below this madrasah, which no longer exists. The Kastel has two pools and WC spaces. It is still in use as a part of Şeyh Fethullah Mosque.
The Kastel of Kozluca: It is located at the south of the Kozluca Mosque. Half of the kastel is above ground with a traditional dwelling constructed over it.. The year of construction is unknown. The restoration of the kastel is completed and it serves as a museum today.The Kastel of Ahmet Çelebi: It is the one with the simplest plan scheme among kastels in Gaziantep reaching today. Currently, the kastel includes only a pool and a well, although earlier records show that it once contained WCs The Kastel is now used as a part of Ahmet Çelebi Mosque.
The Kastel of İmam Gazali: It is one of those that are "completely below- ground kastels". The year of construction is unknown. It has a simple plan scheme which resembles The Kastel of Ahmet Çelebi. There is a rock-carved place on the left side when the stairs are taken down. This place is used for worship. Continuing to step down from the stairs leads to a rock-carved place where only a pool is located. The authenticity has been protected. Restoration work is continuing.
Water structures are important documents of human history because they describe the architectural, engineering, technological information and social and cultural life of the society to which they belong.
Considering the historical water system in Gaziantep; it can be considered important not just as an example of a technology that has been widely used in many places all over the world for a considerable time, but also for its uniqueness in terms of the considerable size of the livas network beneath the city and its special kastel structures. The historical water structures of Gaziantep are important documents of intercultural interaction on the world as well as socio- cultural life and technical knowledge at local scale.
Livas’ have similar construction technology to underground water channels known in many places in the literature as "qanât", which is seen in many parts of the world. Livas’ are used not only for water transport but also in the distribution of water in the city spreading out in a network beneath the entire settlement, which created its vast size and shape.In this framework, Gaziantep livas’ as “qanat” practice in Gaziantep are a part of the common heritage of mankind, and carry unique endogenous values with its own unique formations.
Digging of livas entails an important engineering knowledge. It is a success that the distribution of the water by providing the right slope at every point so as to provide a constant flow in the tunnels of hundreds of kilometers is maintained homogeneously within a certain plan without being too much or too low. It is a hard work to form the tunnels in desired direction by digging rock blocks underground, and to get an active livas through a tunnel in the right direction from the right level of the livas, which is started to be excavated under a building. On the other hand, maintenance and repair work had to be done in order to overcome the deterioration that may occur over time in livas’. Those who work in the maintenance and repair of the livas’ are called 'kanavatcı' in local language. “Livas” word is also unique and is different from terminology used to describe similar underground water structures. The difficulty of digging underground tunnels in the historical water system of Gaziantep has been skilfully overcome and the fact that this system has its own local terminology indicates that the system is the product of an advanced technological knowledge.
Kastels are places that serve as social spaces and meet the toilet, laundry and clean water needs of the people who do not have enough livestock water at home. They are both architecturally and culturally unique structures due to the fact that construction of multifunctional structures underground requires technical and engineering knowledge.
According to the information obtained from the water lawsuit records; it is understood that water usage rules and rights that are valid in the Ottoman period in general and in Gaziantep locally are an important factor in shaping the livas’. The right to use water and the making a connection to the main livas from the structure where water was to be used were subject to the permission, and a water network was created under the city by excavating new livas’ with these permits. As water flows from the structure to the structure; every user on the line had to keep the water clean and use it within the framework of permission which then transformed into a social rule in the society. This form of social interdependence and responsibility, based on water, reflects social norms. The system of livas’ and water structures, which function as a whole in this framework, reflects the social and cultural structure of the society.
Criterion (iii): The Livas’ and kastel system is an exceptional example in terms of the transformation of the management of public water resources into a cultural tradition.
Criterion (iv): Building an underground structure designed to meet the different water use needs of the public, protecting the slope continuously at the same angle in the course of this system developed under hundreds of years while extending and developing network to supply water for every new structure built, discharging the sewage through separate livas’ are all engineering achievements. Kastel is also a significant type of multifunctional structure which is articulated to complex livas system built underground. Livas’ and water structures were not initially designed as an integrated water transport system but later have become a system that functioned as a whole. In this framework, the historical water system of Gaziantep reveals a highly developed, integrated and complex system with the additions made over time.
The documentation of the part between the water source and Alleben Pond has been completed in large scale and components that protect the integrity and authenticity to a large extent are included in the application.
Kastel structures have been registered as “cultural assets need to be protected” in 1972 and some in 1993 within the scope of the Protection of Cultural and Natural Assets Law No. 2863, and they also stays within the urban protection area of Gaziantep registered in 1979. Besides, documentation works of the extant parts of the livas’ system continue. A completed part of the documentation works of the Pancarlı livas line has been declared as the 1st Degree Archaeological Site, covering 5 meters from both sides of the canal. Thus, the parts of Gaziantep underground water system whose documentation are completed have been taken under legal control by the Ministry of Culture and Tourism, the responsible body for preserving the cultural heritage in Turkey. In addition to that, the documentation works of the eastern section of the 1st Degree Archaeological Site on the side of the Pancarlı livas line have been completed and the studies for registration have been ongoing.
The ownership of the structures proposed to the nomination belongs to the Regional Directorate of Pious Foundations, some of which have been taken over by the local municipality. The fact that the structures are not in private ownership is an opportunity for carrying out conservation works in a holistic manner.
Unconscious interventions in the city center resulting from the construction activities after 1950's have led to livas’ being interrupted in places. However, when the documentation studies of recent years are completed, the damaged sections will be clarified and intervention decisions will be taken accordingly.
Measures have been taken within the scope of Gaziantep Conservation Development Plan provisions to protect livas’ and water distribution systems against the risk of destruction of the livas’ by construction activities. According to this; it is required to document the underground remains by means of non-destructive methods before any kind of construction intervention to be made in the urban conservation area. In recent days, it is also the agenda to completely remove the basement floor permit for construction activities in these areas.
Livas’ and kastels, which we know to be used for at least 800 years –although not yet certain-, were used by the Gaziantep people until the 1950s.
During the years passed, underground water tunnels were restored by the municipality in a proper way and the clear water flow to the kastels was provided; and some have been opened for visit while some serve for use within mosque complexes.
In the caves above İhsan Bey Kastel, there is the War Museum built in accordance and in compliance with the original function of the constructions. The livas’ between the Pişirici, Kozluca, İhsan Bey and Fethullah Kastels have been cleaned by the municipality in order to be reintroduced to their original functions.
Recently, researchers in different areas of expertise have been working on understanding livas and kastel constructions. In this context, works are being carried out for the documentation, analysis and preservation of livas’ and kastels, in collaboration between Gaziantep Metropolitan Municipality, ÇEKÜL (The Foundation for the Protection and Promotion of the Environment and Cultural Heritage) and Obruk Cave Research Group, and they are further supported by academic publications.
All these tunnels built underground to bring water from a source in a high place to the lowland have exactly the same basic function, even though their names are 'qanât', 'karez' or other local word. This system that develops from the first millennium B.C. to today can be seen in an area from China to Iran, Yemen, and even Mexico.
This form of water management through qanât systems played crucial role in the development of the Silk Road particularly, in the wider geography. Some systems on this route are still represented in the List or Temporary List (The Persian Qanat in Iran, and Bam and Its Cultural Landscape, Iran on the WHL while Karez System Cultural Landscape in Pakistan, and Karez Wells in China on the Tentative List).
Gaziantep, which is located on the Silk Road too, is an important part of this system for that it represents an important stage in the development of this system. However, other underground water tunnels are mainly aimed at irrigating agricultural land, while they contribute to urban use in some places. The livas’ of Gaziantep, unlike these structures, were excavated mainly to bring clean water to the people of a city and not to agricultural irrigation. Therefore; unlike the other examples, they are dug like a city network circulating all the neighborhoods, and since this clean water is not enough to be taken by the wells only, the intention of the common public use of the water has been built. On the other hand, while the other assets on the route are dated to earlier periods mainly, the kastel structures in Gaziantep are dated mostly to the Ottoman period, while the livas’ are estimated to be earlier. They therefore stand out in terms of historical continuity on the route and contribute to the development of the system with this feature. In this framework, while Gaziantep underground water structures share similarities with other underground water tunnels located in the surrounding geography, it also bears other features peculiar to Gaziantep in terms of construction technique, history, function, form and length.