Endowing money for the construction of a fountain and a water supply line to it was an act of piety which played an important role in Ottoman life. Hardly a sultan, sultan's mother, sultan's daughter, grand vezir, or other august personage did not endow a fountain in expression of their economic, social and political standing, and fountains became an important part of the architectural tradition. Fountains were decorative features of both outdoor public spaces like squares, and intimate indoor spaces in private dwellings, and they reflected the architectural taste and styles of their time.

Surviving documents show that in the sixteenth century in particular the Ottoman government favoured supplying public fountains rather than private homes with mains water. This made the local fountain an indispensable focal point of every neighbourhood. In these introverted neighbourhoods, with their wooden houses with jettied upper storeys, deadend streets, and lanes reflecting their organic evolution, the fountain shaped their unique character. The human scale organic streets wound and turned their way to the mosque square, which was always characterised by a fountain as well as a coffee house and spreading plane tree casting welcome shade. In Istanbul, as in every Turkish city in the past, the local fountain was a hub of social intercourse.

Istanbul was never at any time a city with abundant water sources close at hand, but from the sixteenth century onwards, as the water system was improved and extended, the government began to permit water to be piped into private mansions in the city and along the Bosphorus. The luxury of piped mains water was a privilege requiring a royal patent, and ordinary people were still largely dependent on neighbourhood public fountains for their water, augmented by that obtained from wells and cisterns.

There were two classes of fountain, those for the use of the general public and those allocated to the use of the sakas. Although it was forbidden for the sakas, particularly those who used horses, to fill their water skins at the public fountains, this ban was not always complied with. Documents record frequent quarrels between the horse and foot sakas over access to the same fountain. It was to ensure that local people were not obstructed by sakas from obtaining water free from public fountains that a ban on sakas was incorporated into the inscriptions of some of them at the wish of the founder.

Public fountains were of two types with respect to their source of water supply. The first were supplied from sources harnessed or privately owned by individuals (vakif waters, and mülk waters), and the second were supplied from the mains system (hassa or miri waters). Although fountains varied with respect to the material they were made of, their form, and style of decoration over the centuries, they basically consisted of the same four elements: A tank in which water was stored, and which was a prominent architectural feature in early fountains. In some cases the roof of these tanks was designed to serve a dual purpose as prayer terrace or namazgah, examples being Esma Sultan Fountain in Kadirga and Abdülmecit Han Fountain in Yesilköy. A stone slab known as the musluk tasi or ayna tasi, in which the tap was fitted, and which was set inside an arched niche with decoration in the style of the day. The taps were of two types, those which ran continually known as salma, and those which could be turned off and on known as burma. An inscription carved on the ayna tasi giving the name of the person who had endowed it, and sometimes the source of the water and the date of construction. Beneath the tab was a basin known as a kurna, and to either side small raised areas where people collecting water could sit or rest their vessels while they waited. The design of these elements varied with the architectural fashions of the times, the approach to city planning, and the personal tastes of the founder. Fountains in the form of columns (Ahmet Aga Fountain built in Çengelköy in 1854) were an unusual type limited to a specific period, for example. Others were designed like the façade of a building and had a monumental effect on the urban texture (Bezmiâlem Valide Sultan Fountains in Yildiz). With the beginning of western influences on Ottoman architecture, it became common to build fountains in squares of commercial, social or ceremonial importance, often next to monumental mosques and their complexes, and situated at points where striking vistas of the city were to be obtained. These often freestanding fountains in the form of miniature pavilions had façades reflecting western architectural fashions, and clearly setting out to rival their western equivalents and to impress the viewer with the modernity and hence power of Ottoman architecture (the two Ahmet III fountains outside the Imperial Gate at Topkapi Palace and in Üsküdar respectively, Mahmud II Fountain in Tophane, and Bezmiâlem Valide Sultan Fountain in Maçka). Others were an integral part of building complexes, or formed an eye-catching feature in the façade of a building.

In line with changes in materials, form and style over the centuries, changes in the abovementioned elements of the fountains were as follows. In the fifteenth, sixteenth and seventeenth centuries the ayna tasi which carried the tap was usually plain and set in a classical arched niche. The inscription was located above the tap, and below was the basin flanked by raised platforms. Fountains of these centuries also had water storage tanks. In the eighteenth century, when fountains built of hewn stone made way for marble, this type of façade altered, as the ayna tasi began to acquire a lavish repertoire of carved decoration, including roses, vases of flowers, and plates of fruit set in decorative arches. The formerly deep alcove niches became much shallower, and baroque style shell motifs appeared for the first time. Other changes also took place in fountain architecture in the eighteenth century. The fountain became taller, and the section bearing the inscription became a separate part of the façade, which was sometimes shaded by baroque style eaves.

The first examples of the combined sebil (kiosk for the distribution of drinking water to passers-by in cups) and fountain in a single structure appeared in the seventeenth century (Hatice Turhan Valide Sultan Fountain and Sebil, 1663), and became more common in the eighteenth century. Similarly the monumental meydan fountains-independent structures designed like pavilions-became fashionable, such as Ahmed III Fountain in front of the Imperial Gate at Topkapi Palace.

In the nineteenth century, with a more reliable supply of mains water, fountains no longer needed storage tanks, and this sparked off new designs. Among these were fountains with neo-classical façades. In the very early period most fountains had had permanently running spouts, but when the Kirkçesme system was being built during the reign of Süleyman the Magnificent taps which could be turned on and off as required were introduced, so preventing both the wastage of water and permanently muddy streets.

Fountains were diverse, both as regards their structures and their functions, and twentieth century writers on the subject have classified them in numerous different ways. Often the name of a fountain tells its own story, as in the case of the Ayrilik Çeşmesi (Fountain of Departure) which was situated at the point where those accompanying the imperial procession to Mecca, the army setting out on campaign and caravans heading eastwards, and pilgrims to Mecca bade farewell to their loved ones when departing from Istanbul. Similarly, Selâmi Çeşme was a fountain at another point where travellers arriving in the city were welcomed (selam meaning greeting), and also departed. Bostanci Fountain was named after the bostancibasi, the head of the security organisation which checked arrivals and departures from the city. Others referred to characteristics of the fountain itself, such as those known as Çatal Çeşme (fork fountain), which were usually situated at corners and had two or three faces, each with its own tap facing in a different direction. In this study they have been classified undere the following headings according to their positions and purpose.

Wall Fountains: These are fountains built into the walls of buildings, gardens or courtyards. Their storage tanks, where these exist, are located behind the wall. They are also referred to as single-face or façade fountains.These were built in various styles between the fifteenth and early twentieth centuries.

Corner Fountains: Fountains on street corners mainly had a single face in earlier centuries, but in later times examples with two or three faces were constructed. Since the corner edges were liable to get knocked and damaged by laden carts and other vehicles, these were often bevelled up to a certain height, a feature known as çalköse.

Meydan (Freestanding) Fountains: Located in squares and parade fields, this type of fountain is a freestanding building in the form of a miniature kösk or pavilion. They were an innovation of the eighteenth century and among the earliest examples of western influence on Ottoman architecture. In general they had four sides. Elaborate examples like the monumental Ahmet III Fountain outside the main entrance of Topkapi Palace built in 1728 had sebils at the corners where passers-by could drink water from cups filled by attendants, as well as taps for filling large water containers. Some of the meydan fountains had taps in a single face (such as Mahmud II Fountain in Boyaciköy dated 1837) or two faces (such as Hekimoglu Ali Pasa Meydan Fountain in Kabatas dated 1732, and Saliha Sultan Fountain in Azapkapi dated 1732).

Fountains Designed as Part of Sebils: Sebils were kiosks where water, sweetend fruit drinks known as serbet and fruit juice was distributed to passersby. The earliest example in Istanbul is Efdalzade Sebil dated 1496 (Kumbaracilar 1938; Ünsal 1986; Urfalioglu 1989). Just as meydan fountains sometimes incorporated sebils, so sebils sometimes incorporated fountains, and the two types converged if the building was freestanding. The earliest surviving example of this type is the Hatice Turhan Valide Sultan Sebil and Fountain dating from 1663. This type was particularly popular in the eighteenth century, leading some researchers to regard it as a distinguishing characteristic of this period. Although the existence of an earlier example in the seventeenth century- Hatice Turhan Valide Sultan Sebil and Fountain-demonstrates that as a type it did originate prior to the eighteenth century, the fact that this is the only surviving example makes it difficult to determine how widespread such fountains were in the seventeenth century. Sebils incorporating fountains, which first appear in the seventeenth century, were usually designed with fountains to one side (Hatice Turhan Valide Sultan Sebil 1663, Sadeddin Efendi Sebil 1741, and Damat Ibrahim Pasa Sebil 1719) or on both sides (Hamidiye Sebil 1777 and Koca Ragip Pasa Sebil 1762), fountain and sebil forming a unified architectural composition. In most instances they were located at the main entrance gate to mosque complexes (Hasan Pasa Sebil 1745, Ahmediye Sebil 1721), or at prominent street corners (Besir Aga Sebil 1745) providing visual emphasis and architectural focal points in the form of a selfcontained monumental feature. With the emergence of the monumental meydan fountain in the eighteenth century, the sebil was used as an element which lent a further enrichening element to the design (Ahmed III Fountain at Topkapi Palace, 1728, and Saliha Sultan Fountain 1732).

Namazgâh Fountains: A namazgâh was an open-air prayer terrace constructed for the use both of travellers on caravan routes, and at excursion places on the outskirts of cities. Fountains next to these provided the water which worshippers needed to perform their ritual ablutions before praying and water for them and their animals to drink. There are very few surviving examples of namazgâh fountains, in which the prayer terrace was constructed on top of the fountain's storage tank (Esma Sultan Namazgâh Fountain in Kadirga, Bezmiâlem Valide Sultan Namazgâh and Abdülmecid Han Fountain in Yeşilköy, Sadrazam Mehmed Pasa Fountain at Topçular between Edirnekapi and Rami, and Uzun Çeşme in Kasimpasa). Our knowledge of these fountains and their architecture is limited in scope. However, from maps of Istanbul's water systems and engravings we see that fountains at halting points had broad eaves to protect those using them from rain, snow and sun, and architecturally resembled urban fountains with troughs beneath the taps. In some cases the namazgâh platform was situated on top of the fountain itself (Anadoluhisari Fountain, seventeenth century, Esma Sultan Fountain in Kadirga 1779), or the mihrap stone (indicating the direction of Mecca) was incorporated into the fountain structure (Vezir Mehmed Pasa Fountain opposite Sulukule Gate outside the city walls 1589).

Those namazgâh fountains which once existed in Istanbul and its outlying suburbs which we have been able to identify, including the few still standing, are as follows: Üçler Mevkisi Namazgâh Fountain west of Atmeydani (1516), Çeşmebaşı Namazgâh Fountain in Bayrampasa, Vezir Mehmed Pasa Namazgâh Fountain (1589) opposite Sulukule Gate outside the city walls at the edge of the Edirnekapi-Topkapi road, Sadrazam Mehmed Pasa Namazgâh Fountain (1617) at Topçular between Edirnekapi and Rami, Kasimpasa Uzun Çeşme (date uncertain), Okmeydani Namazgâh Fountain (date uncertain), the fountain beside Bezmiâlem Valide Sultan Namazgâh in Maçka (1839), Abdülmecid Han Fountain at Bezmiâlem Valide Sultan Namazgâh in Yeşilköy (1842), Çatal Çeşme in Suadiye (1550), Toplarönü Namazgâh Fountain in Anadoluhisari (seventeenth century), Mehmed Bey Namazgâh Fountain at Sultaniye Meadow in Beykoz (1765), Ahmet Aga (Ayrilik) Fountain in Haydarpasa (1741), Selâmi Çeşme Fountain in Kadiköy (1800), Sultan Mahmud II Han Namazgâh Fountain in Bostanci (1831), and Adile Sultan Fountain in Dudullu (originally built in 1730 and renovated in 1891).

Although most of the fountains built at former menzil points (halting points for caravans) in the Asian districts of Istanbul were still standing in their original locations until recent years, their namazgâh terraces have been demolished in the course of new building. The fountains which remain are often hardly noticeable, squeezed between new buildings, as in the case of Mahmud II Han Fountain in Bostanci, Ahmet Aga (Ayrilik) Fountain in Haydarpasa, and Selâmi Çeşme Fountain in Kadiköy.

Indoor Fountains: Indoor fountains in palaces and mansions served multiple functions. As well as being sources of water for washing and ritual ablutions the sound of running water was a pleasant feature lending a mood of tranquility, and in addition served to prevent eavesdroppers from overhearing confidential conversations, and provided a decorative feature in the room. Indoor fountains were supplied either from the public water system, or by privately owned water lines (mülk sulari). They featured in buildings from the fifteenth century onwards.

Column Fountains: This type of fountain in the form of single columns became fashionable from the eighteenth century onwards, and examples are to be seen in diverse settings ranging from mosque courtyards to quayside squares. The earliest example is Haci Besir Aga Fountain (1737), in the courtyard of Kocamustafapasa Mosque, although the majority date from the nineteenth century. The columns sometimes had finials in the form of stylised cabbages (Çengelköy Lahana Fountain). They reflect the fact that the large water storage tanks of earlier times were no longer needed thanks to new and more reliable mains water lines which could supply the fountain tap directly. Inspiration for the column design was almost certainly of Western derivation, and probably set out to provide Istanbul with an equivalent of the monumental statues which adorned European cities. Conceptually they took over the role of the meydan fountains as striking focal points of urban squares. Examples are the Mahmud II Fountain in Tarabya (1831) and Kavacik Fountain (1837).

Selsebils: The selsebil was an ornamental cascade fountain located in gardens of grand homes. The marble basins of graduated size were set into an upright slab of stone known as the zank tasi. The water poured either into a final large basin or garden pool. These structures were not intended to supply water needs, but as a decorative architectural feature enhancing the space where they were located. Those in interior spaces, like room fountains, were intended partly to create a pleasant splashing sound of water in the room and at the same time make it possible to hold private conversations without being overheard while also serving an air conditioning function by cooling the air. Those located in the openair of pavilions and waterfront houses had similar functions, and in addition provided water for birds.