Available online http://amq.aiqua.it ISSN (print): 2279-7327, ISSN (online): 2279-7335 Alpine and Mediterranean Quaternary, 31 (2), 2018, 195 - 205 THE STRATIFIED GROWTH OF CHIETI FROM ROMAN TIMES TO TOMORROW: A NEW, GEOLOGY-BASED CONSCIENCE IN CITY PLANNING AND RENEWAL Silvano Agostini Soprintendenza Archeologica belle arti e paesaggio dell'Abruzzo, L’Aquila, Italy Corresponding author: S. Agostini <silvano.agostini@beniculturali.it> ABSTRACT: Human settlement grew around and at the foot of the hill of Chieti partly conditioned by the local geological and geo- morphological characteristics, and partly transforming them. The hill is vulnerable, due to its geological structure and geomor- phological evolution. Following the stratification of human activities and the intense construction activity on the hill, particularly after the Second World War, monuments and both ancient and recent buildings suffered several stability issues. Three of the city’s most important archaeological monuments are taken as emblematic of the interplay between local geology and human impact. The analysis shows that sound knowledge of how Quaternary geological processes operated in time and space needs to become a permanent part of urban planning policy and urban renewal. In fact, the latter have to be strongly sensitive to the equilibrium between the impact of human activities and environmental geology, and able to predict how existing infrastructures respond to the effects of climate change (e.g. new rainfall regime). Geological culture is the basis for redesigning the city with less, or no, use of concrete and more widespread use of bioengineering. . Keywords: Urban geoarchaeology, Southern Italy, Abruzzi Periadriatic region, Plio-Pleistocene marine deposits 1. INTRODUCTION The geological and geomorphological characteris- tics of the town of Chieti (Teate Marrucinorum in pre- Roman and Roman times) have conditioned and have been partly transformed by the impact and spread of human settlement around and at the foot of the hill. “Super omnia, quae umquam audita sunt, erit prodigium in nostro aevo Neronis principis ruina factum in agro Marrucino, Vetti Marcelli e primis equestris ordinis oli- veto universo viam publicam transgresso arvisque inde e contrario in locum oliveti profectis”, Plinius Secundus C., Naturalis Historia Liber XVII 245. "A portent that will eclipse all those ever heard of occurred in our own day in the territory of the Marruccini, at the fall of the em- peror Nero: an olive grove belonging to a leading mem- ber of the equestrian order named Vettius Marcellus bodily crossed the public highway, and the crops grow- ing on the other side passed over in the opposite direc- tion” (Rackhaman, 1961). These words clearly show that the hill of Chieti was known to be highly vulnerable and unstable already twenty centuries ago; for its char- acteristics it was the object of wonder, chronicles and a memory to be passed on. The vulnerability of the hill on which Chieti stands is determined by its natural geologi- cal structure and geomorphological evolution. The geo- logical context is not exclusive to the town; in fact, it characterises the entire mid-Adriatic coastal hill belt (Centamore & Nisio, 2003; Centamore et al., 2003). Owing to its vulnerability, the hill of Chieti always reacted directly or indirectly to the stratification of human activities with instability phenomena which affected the built fabric at any time and no matter what construction technique was used. We must first observe that hydro- geological instability turns into a major problem when urban space is developed, following a plan, or not, with- out any background knowledge of geology. In other words, repeated out burts of instability have always oc- curred not only due to the mistaken belief that the hill’s geological processes are static, rather than dynamic, but also adopting wrong strategies to contrast the unbal- ances caused by human impact which induced further acceleration of the processes. This error could also be perpetuated in the future. It is worth emphasising that the absence of geological culture does not imply lack of technology and technical solutions (land defences, rec- lamation) aimed at preventing and limiting the risks in- herent in the management of Chieti’s subsurface insta- bility; rather, there has been prolonged absence of ma- terial and cultural responsibility in land management. Today, special attention is devoted worldwide to the quality of life, not only in urban areas. This implies tack- ling hydrogeological issues, as well as the risks posed to property, and to life itself. We also need to plan and implement more appropriate, effective and all- encompassing prevention measures and broad interven- tions. Administrators and citizens need to recover a ne- glected geological culture, but this is no longer enough. Much more must be done. https://doi.org/10.26382/AMQ.2018.13