Seite - 23 - in The Power of Urban Water - Studies in premodern urbanism

2 FromNature to Topography 23 Fig. 6:Concordia, urban layoutwith canal separating secondand third rowof insulae, fromsouth. Aslightly different, yetmore immediate role for theurban topography canbediscerned in the colonyof Iulia Concordia.Here, as innearbyAltinumorMilan,watercourses playedan impor- tant role in shaping the local character of the settlement established between two small rivers that received its almost uncompromising orthogonal layout during the later 1st century BC. A 9mwidecanaldividingthecityarea is,however,a local feature thatdistinguishes IuliaConcor- dia clearly from both citiesmentioned. Connecting the two small waterways surrounding the city, the canal was, in a remarkably consistent way, embedded into the urban layout: it was adjusted to the street grid and accompanied one of its decumani as an inner-city east-west waterway.Knownonly fromlate 19th centuryexcavations, itsprominent role for the localurban space can only be specified by consulting old plans and descriptions35 (Figs.6‒7). While the south sideof the canalwas formedbyonly a simplewall, its north side receivedamore elabo- rate – and spacious – architectural definition: here six wide stone steps connected the canal with theaccompanyingdecumanus.Although theexactdepthandheightof these stepsarenot known, the 19th century drawings anddescriptions indicate anapproximate total depth of 9m and a height of altogether 1.8m.36 With a length of over 750m and interrupted only by the bridges of the cardines crossing the canal, these downrightmonumental stepswere one of the most strikingarchitectural featureswithin the citywalls. 35 Bertolini 1880;Vigoni 2006;Vigoni 2013. 36 Vigoni 2006, 459f. fig. 5;Vigoni 2013, 97. Should the steps indicated in theplangivenbyBertolini 1880,pl. 14 be true to scale, the six stepswould correspondapproximately to thewidthof the accompanyingdecumanus.