Ecocity World Summit 2009 Proceedings 1 BUILDING IN ALREADY BUILT- AREAS Francesco Domenico Moccia University “Federico II”, Department of Urban Design and Planning, Naples, Italy, fdmoccia@unina.it ABSTRACT In Europe the land resource is less available than any other; nevertheless, the sprawl has occurred and soil consumption ranks among the worst planning problems. One of the most pervasive objectives of planning is to save soil permeability against an increasing demand of housing, services and plants. The solution to this dilemma seems to be to build on already built areas and improve urban density. This statement is becoming one of the main trends of the main European Metropolis with oil costs and energy production difficulties. Europe has also signed the Kyoto Protocol and have dictate clear objective to all its countries in the field of energy saving and green house gasses emissions. Build industry will give an important contribution making available innovative technologies, but a new urban model able to minimize commuting, shift to the mass transit mode, concentrate functions is also needed. University Federico II urban planning workshop focused on underused land as large commercial centres parking lots (with railway access), railway tracks, vacant industrial areas, to find how they could be turned in multifunctional high density housing complexes while restoring creeks and revamping natural areas. In these new districts there will be many devices to produce energy from renewable as wind, sun, and geothermal. Urban infrastructure will be devoted to differentiate and collect garbage, distribute heating, commute door to door. Four projects in the metropolitan area of Naples will be presented. Keywords: densification, eco-efficiency, green infrastructure, poly-centricity, mix use, high density, city planning, metropolitan area, Neaples, carfree city, brown-field INTRODUCTION This paper draws from two years workshops on city planning of the University “Federico II” Planning master program some ideas and projects elaborated on the issue of ecocity. The framework of this work is based on the UN documents on climate change, on the European Union strategis of mitigation and adaptation to global warming (European Communities, 2008) and on some theories and models of carfree (Crawford, 2002, 2009; Legambiente 2009) and sustainable city (Register, 2006). The task is to identify some technical principles whose application could change cities and metropolis so that mankind could face challenges of future fossil fuel shortage joined to the consumption to many other natural resources. The first two paragraphs sketch an essential framework of ideas and theories that define and give an aim to workshops. There is any pretence to make a full review of the literature on the subject neither to discuss the rightness of positions and statements. It is given just a short list of issues that require