Aqueducts were built for several reasons. The most important one was, surprisingly, not the need for drinking water; wells and cisterns could in most cases provide this. Bathing was a major element of roman culture, and baths need running water, and a lot of it. The mean reason for building most of the aqueducts was therefore to provide roman baths with fresh, running water. Of course, drinking water was also supplied in this way, and this was without doubt the second important reason to build these structures. A third important reason, like in modern times was prestige and political influence; many aqueducts were built because neighboring cities already had them, and many were financed by rich roman citizens who wanted to expand their influence, commonly the Emperor himself. Aqueducts were expensive structures to build, and the undertaking of building one can only be compared with building an airport nowadays.