Just as Roman roads survive in great numbers in Turkey, so do bridges, some of them still in everyday use (a complete listing would be useful), as at Aizanoi (SB6.4). Like aqueducts (another kind of bridge), they survive because of the strength of their construction, being generally of poured concrete with stone-block facings. As engineering feats, it is arguable that the bridges in most of Turkey presented fewer challenges than in Northern Europe, where rivers always had water in them; in much of Turkey, work could proceed more comfortably during the dry season.
It is particularly noticeable how later road and bridge engineers (in Turkey as elsewhere) were bound or helped by what their forbears had done. The line of a road, and hence the positioning of a bridge, was fixed, and there was little point in altering them by much. Two good examples are on the approach road to Aspendos, and where the aqueduct crosses a river between Seleukia in Pamphylia and Side. At the first site, a 13th century Seljuk bridge has replaced a 2nd century Roman structure, the remains of which are visible nearby. Near Seleukia, and not far from the Manavgat waterfalls, stand the remains of an aqueduct crossing the river - an aqueduct which, a little further upstream, is in remarkably good condition. Seljuk builders, when constructing their bridge, leant their work against the Roman aqueduct, and also re-used some of its stones.
If rivers were useful water carriers, they could also form an obstacle to town planning when they got in the way of building. The Romans simply did not allow this to happen. At Pergamum, the river is arched over and led underground through the length of the lower city, and the houses and monuments built on top. At Nyssa, the central gulley (not deep enough to be termed a ravine) was treated as if it did not exist, by vaulting it over to support both the "agora" in front of the theatre, and part of the large stadium. Little survives on site, except for the 150-metre-long vaulted tunnel at the bottom of the gulley containing the river, which is easily negotiable in the dry season. From the lie of the land - with a hill to the north with the famous library and, in front of it, the theatre, and then substantially flat ground to the south of the gulley, it is hard to argue that any such engineering work (other than a bridge over the gulley) was necessary: rather, it was desirable - a demonstration of difficulty overcome with ease.
Water is a luxury item as well as a necessity. Certainly, the larger the community, the more water was needed - for agriculture and animals as well as for day-to-day household needs. This does not normally require the use of aqueducts to bring the water from afar, since communities naturally settle only where water is obtainable. But it would be as erroneous to try and make any fixed equation between the number of inhabitants and the amount of water "required", as it would between the size of Gothic cathedrals and that of local populations. Perhaps, therefore, we should think of water in the Graeco-Roman world (just like monumental architecture in any period) as a political as much as a physical necessity: that is, a city displayed not merely its technology but also its wealth by having a precious commodity running through its streets, and sometimes even available at the turn of a tap - a feature which would be the envy of at least half the world today. Priene, for example, with the end of an aqueduct and storage-cum-settlement reservoirs well above the inhabited section of the city, could distribute water in earthenware pipes through its streets taking advantage of the steep slope on which the city was built. We can parallel this "conspicuous consumption" or "prosperity symbolism" with examples from the mediaeval West, where fountains (as, for example, the Fontana Maggiore at Perugia) were so often the central focus of the main town square, suitably decorated by the best sculptors of the day. Although the fountains themselves were surely evidence enough, the city fathers at Sardis put up an inscription detailing not only the public fountains in the city, but also their output (Hanfmann 1975, 27). Overflow from fountains presumably fed public toilets which are such a convivial feature of many Roman sites - for example, those below the theatre at Side (4), which are indeed adjacent to a fountain facing onto the commercial agora.
No settlement can do without water. I write water rather than running water, because some settlements, especially those on high ground, make do with cisterns, as on the acropolis at Perge (as discussed above); or at Syllium, where the acropolis was inhabited; or indeed at Pergamum, where they were presumably used as holding tanks for regulating the supply to the fountains (since the acropolis was supplied by an aqueduct via a siphon). The most-visited example of a "city" surviving by run-off water is the island of Delos: it is covered with truly huge cisterns and, in addition to enormous "public" cisterns, most houses harbour at least one private supply of no less than four metres in depth under their mosaic or rubble floors. There are plenty of sites in Turkey which also lived from cisterns, sometimes supplemented by springs: Cyaneae, high on its mountainside; Seleucia in Pamphylia, where a very large cistern stands next to the agora; Kadarinda, still difficult to get to, which appears to have the whole of its agora area on the very top of its hill as a series of large cisterns, paved over, and feeding the settlement below; or Elaiussa-Sebaste, where plenty of water runoffs feed cisterns in the limestone (SB6.5). Such arrangements are for relatively small communities - just as river water would serve for daily needs for those settlements on lower ground. But as soon as large-scale public works (especially fountains or markets) became a priority, piped water was essential. The most famous cisterns are in Istanbul, and some of these - the Basilica Cistern and Binbirdirek - are monumental both in scale and because they are supported by a forest of columns.
From here you may also go to The Preface, The Introduction, Archaeology in Turkey, Building for Splendour, Town Planning, The Architecture of Work & Leisure, Religion: Temples & Special Sanctuaries, Funerary Art & Architecture, Decline & Renewal, The Conclusion, The Bibliography, or The Table of Contents