Strolling through the cemetery of Montparnasse in Paris, I fantasize a poker game with an ideal community of the defunct that includes Marguerite Duras, Charles Baudelaire, Delphine Seyrig, and Samuel Beckett. Their modest burial markers rest alongside the ornate aedicules of the proud and powerful, belle époque generals and financiers. Looking around at the densely packed lanes lined with tombs, there seems to be no room left. The necropolis is so crowded that for a moment I have the infantile notion that no one else will be allowed to die. The Montparnasse cemetery is right in the midst of one of the busiest parts of the Left Bank, and to enter is to escape from the tedium of daily life, a place to contemplate the life of the past. In the background rises the immense black, glass-clad tower of Montparnasse, a soaring catacomb for modern offices. Life goes on in the city, overlooking the cemetery, but, as I will try to show, it was never the city itself that was alive.

In fact I am often convinced while visiting cemeteries that the only reason the city became a place is because someone died there. René Girard in his theory of the scapegoat suggests that architecture began with stones used to lapidate a victim. «In the end», says Girard, «the tomb is the first and only cultural symbol». By extension, the city, from its origins, has had the primary function of being a memorial to the dead. Nine millennia ago in Jericho, the layers of neolithic hovels were built directly on top of the burial sites of the ancestors to keep the memory close at hand. In ancient Egypt, the only buildings of true permanence were pyramids and funeral temples. Castel Sant'Angelo, built in 125 as the mausoleum for Emperor Hadrian, still dominates the banks of the Tiber as Rome's most invincible pile of masonry. The necropolis is in truth the real city, and the ephemeral world of traffic and commerce, the expendable realm of residences with TVs, computers, and refrigerators, is a mere shadow of it. Still we continue to call the places where we live «cities», and think of them as being alive, in as much as they support life. A city like Barcelona seems very lively, while one like Houston, seems not so. But this is at most metaphorical opinion. The city has always been dead and in many ways was intended for the dead.

That said, I must address the matter of the presumed «death of the city», which invites automatic associations of disaster: the meltdown of Cernobyl, kamikazes in New York and Madrid, the bombs of Baghdad and Kabul, the floods of Dakka and Dresden, the earthquakes of Kobe and Los Angeles, the hurricanes in Miami and Havana. There is a grand history of urban catastrophes, natural and anthropogenic (and even theogenic, if we consider the fate of Sodom and Gomorrah). Many cities seem to have disappeared with a minimum of trauma, the neolithic Anatolian city of women, Catal Hoyuk, for instance, was apparently abandoned without violence in the fifth millennium, as was the ancient Mexican cult site of Teotihuacan around 200 AD; the ancient capital cities of Tell-el-Amarna and Khorsobad were both abandoned with the death of their respective rulers. Although the cities we know at this time seem so intransigent, and it is hard to imagine their disappearance, most cities in history at some time stop supporting life. The planet is studded with remarkable monuments to cities that have expired: Ur, Angkor Vat, Machu Pichu, Palmyra, Fatehpur Sikri. But of course it was never the city itself, which is inert and inorganic, that died. No matter how damaged it might have become, like Pompeii buried in volcanic soot, or London reduced to ashes, the city as a place remained, rooted to its genius loci, or spirit of place. It was life forms that left these places. In most cases, such as post-conflagration London in 1666, life returned almost as soon as the crisis was over. Jerusalem, for instance, the oldest continuously inhabited city in the world, has been destroyed 17 times; on one occasion, Emperor Hadrian, after razing the city, decided to refound it with a Roman plan and a new name, Elia Capitolina, in the attempt to erase its historic identity and its antipathy to the Roman regime. But despite the repeated destruction, life has somehow always returned to Jerusalem, continuing to this day to be a perpetual source of both inspiration and enmity.

To consider the historical landscape is a bit like visiting the cemetery of Montparnasse. It is dense with shrines to towns arrested in time that I have heard of, or in some cases visited, a necropolis of the world's cities, inert outcroppings that mark time with their shadows. Like Montparnasse, there seems to be no room left, and yet life goes on and cities continue to grow at a terrifyingly incremental pace. In the case of the dead cities of history, I can surmise that life forms leave them for three reasons. But, as I will try to convince you, there is an underlying metaphysical condition today that we can call «the death of the city», that reaches beyond any teleological explanation of why life stops.

Among the causes of urban demise, there are the traumas of natural catastrophes: fires, floods, earthquakes, volcanoes, and hurricanes. Humans cannot usually be identified as directly responsible for the damage (although Suetonius liked to blame Nero personally for the great Fire of Rome in 64 AD). Where humans are most at fault, however, is in the poor choice of sites to settle and the recourse to erroneous building technologies. To situate Pompeii at the base of Vesuvius was an obvious risk, as it still is, and now there are a thousand times the number of inhabitants living in danger. Mike Davis comes to similar conclusions for the siting of Los Angeles, which is doomed to earthquakes, forest fires, flash floods, droughts, perhaps tidal waves, not to mention the immanent threat of social strife.

Natural calamities are followed quickly by anthropogenic disorders, such as, again, fires (this time by bona fide arsonists), migrations, hydraulic crises, famines, plagues, even unemployment. The formidable first city of Ur exhausted its capacity to produce sufficient food, suffering from the salinization of the overworked soil. The 16^th century Mughal capital of Fatehpur Sikri was unable to supply sufficient hydraulic resources to support a large population. The center of America's automotive industry, Detroit, was severely incapacitated by the new flexible economy of the seventies, and vast sections of its urban tissue were transformed into vacant ghost towns. The demise of the nuclear power plant in Cernobyl in 1986 proved to be the most dismal elimination of urban life through human error, and still threatens to be, as the cement sarcophagus continues to develop cracks opening to the 200 tons of molten uranium inside. This destiny of urban catastrophe is what Paul Virilio so astutely catalogued as the culmination of the human condition in his exhibition Ce qui arrive.

And then, of course, the greatest anthropogenic problem, warfare, can stand by itself as a cause, with the countless instances of exterminations due to civil wars, international wars, colonial occupations, terrorism, and acts of vindictive aggression. Beirut, after its 15-year orgy of destruction is depicted by photographer Gabriele Basilico in 1991 as seemingly incapable of supporting life. The first atomic bomb at Hiroshima, on August 6, 1945, which eliminated 60,000 lives in less than a minute, made the city seem even less habitable amid the radioactive rubble. The Mongols' decimation of medieval Baghdad left a trail of blood across Asia, just as Bush-Cheney's contemporary effort to replay it in the name of «prevention» has left a trail of petrol leading back to New York and Houston. But in all these cases, after a period of transition, life forms rather unselfconsciously return to the genius loci. Very few cities that have been destroyed by warfare have not been revived. Even ancient Rome's dreaded rival Carthage, after two centuries of wars, and its complete annihilation, was rebuilt on a Roman plan, and survived until the 7^th century. So I can reiterate, cities are by definition dead, and it is merely the life that inhabits them that is animate and variable.

The best image that I think of to capture the sense of the death of the city, one that corresponds to my vision of the world as a cemetery for cities, is a ponderous work of land art by Alberto Burri, Il Cretto at Gibellina. This small hill town of 5,000 people in the southwestern hinterlands of Sicily was completely destroyed by an earthquake in 1968. Its residents were moved to temporary sheds nearby, and with the city in ruins, a plebiscite determined to transfer the town to the valley 15 km away, where it could be close to the major infrastructures of train and autostrada. The Italian state promised to induce industries to move to the area to provide new forms of employment, but like many political promises they were not kept. The mayor of the town, Ludovico Corrao, a communist lawyer with many acquaintances in the arts, during 25 years put together a cultural program integrated with the construction of the new town that has generated more public works of modern art pro capita of any city in the world. The architecture and art of new Gibellina, however, demonstrate the benefits and defects of modern art in public places in general, seen in many other more metropolitan urban contexts. But what has become of the new Gibellina seems much less significant for my purposes than what became of the old town.

Burri's response to the site and the situation was to cover the entire town with a meter and half of concrete, leaving a tissue of pathways like the lines of an eroded tablet of clay (thus, Il Cretto), gaps that do not trace precisely the old streets of the city but look generically like those of any small Mediterranean town. This intervention proved to be at once pragmatic and spiritual, as the ruins of the town, which were a public danger, were gathered by bulldozers and covered over by the blanched concrete forms, while the concrete masses themselves resemble colossal sarcophagi, devoted to no single individual in particular but to the collective urban existence that came to an end. The largest piece of land art ever realized - it covers 40 hectares - Il Cretto, by mounding over the town, conveys a universal expression of grief. It remains a memorial to the lost city, inert, inorganic, yet still hauntingly evocative of the genius loci. An icon of the notion that the city is dead.

To speak of the «death of the city» today comprehends the traumatic breaks in life forms mentioned above but ultimately addresses the ontological question of whether a phenomenon once known as «the city» can still exist. And although this essentially semantic issue does not concern the dramatic loss of human life in wars, earthquakes, and nuclear disasters, it is nonetheless the most disturbing theory, because it threatens the interpretation of how we live in the present. The end of cities was predicted, without great philosophical pretensions, by the American architect Frank Lloyd Wright in the thirties, when he advocated the «disappearing city», an endless rural settlement with good transportation infrastructure and occasional urban functions at the freeway interchanges. The current advance of urbanization and demographic escalation, coupled with the increasing ephemeralization of communication and transport, has in fact led to a form of urban life that in Wright's words is: «everywhere and nowhere».

Only 100 years ago, less than 10% of the world lived in cities; today more than 50% live in what can be called «urbanized territories». If the trend toward urbanization continues, by 2050 it is estimated that 70% will inhabit such conditions, and if time endures for a few more generations after that, it is possible that the entire world will be urbanized. It follows that the success of sprawled urban development will lead to a completely interconnected system that converts the planet into a single world city. Because at the same time of the great increment in urban populations, the divisions between cities are disappearing. Jean-Jacques Rousseau was perhaps the first to identify such a phenomenon, when he noticed that mid-18^th century Switzerland seemed to be a single city occupying the valleys, interrupted sporadically by the natural features of the mountains and lakes. The contemporary megalopolis was theorized and named by Jean Gottman in the fifties when considering the urban consolidation of Boston, New York, Philadelphia and Washington, and has since been identified throughout the more developed parts of the world. Currently the largest megalopolis, Tokyo-Yokahama has a population greater than Switzerland, estimated at 33 million inhabitants. Paris during the past 40 years has followed a planned development of occupying all of the territory of Ile-de-France with about 12 million. London since 1944 has grown somewhat according to the polynucleated plan of Patrick Abercrombie into a territory with a 56 km radius and a population a little larger than Paris. In 1956, Holland recognized the existence of the Randstad, its «rimcity» of 12 linked cities surrounding a green core, now with a combined population of seven million. The towns of the post-industrial Ruhr Valley, 60 km in length, are currently considered a single urban system for 5.5 million. In Italy, Eugenio Turri has coined the expression la Megalopoli Padana for the agglomeration of Genoa, Turin, Milan, Bologna, and Venice. What is commonly referred to as Los Angeles is in fact made of a federation of 43 municipalities for 17.5 million people. Metropolitan Barcelona, which currently hosts 4.5 million, or 70% of Catalonia's population, consists of 218 municipalities. Through networking relationships, Joan Trullen projects that during the next generation we can expect the urban union of Barcelona with Tarragona and Girona. In the next generation after that, one can anticipate the spilling between Madrid and Barcelona, into an eventual Madelona.

Despite the progress of this meaning of the «death of the city» through both dramatic changes in dimensions and telematic ephemeralization, the city still exists as a form, we still use the word in reference to places, and we still feel a certain nostalgia for the concepts of civic values and community that were attached to the phenomenon. The idea of the city connotes responsibility and can serve as a corrective to the ungovernable urban sprawl that is occurring. The more the city dies, the more urban sprawl expands, the less societies have been able to deal with their impending ecological problems. Just as the visit to the cemetery infers a respect for the dead, so the interest in the city implies respect for this civic consciousness. The demise of the city of Venice can be used as the parable for the ecological demise of the planet. The city is threatened with both sinking and flooding, due to the rising seawater caused by global warming and the lowering water table caused by industrial exploitation. Venice for centuries was never attacked militarily because of its superior strategic placement on 60 floating islands in a shallow lagoon. It needed no walls for defense. The thick clay soil of the islands insures their impermeability as they hover over fresh water channels that are below the level of the lagoon. Venice's nickname «La Serenissima» conveys the idea of a city that is unassailable and immutable. The architecture of the city was singularly free of defensive iconography: joyful, permeable and open.
During the late 20^th century, to maintain the economy of the aristocratic image of a city of palaces, the lagoon's coast at Mestre and Marghera was completely destroyed by industrial development, creating the densest and most polluted petro-chemical district in Italy. The water that is still being sucked from the underground sources for industrial purposes has jeopardized the stability of the islands. Meanwhile the regular floods, up to 100 days per year, have made Venice an even more amphibious place than it was in its origins.

After 20 years of preparation, the solution to prevent the flooding of Venice has been approved. Known as the «Moses Project», it would create a barrier that automatically springs into place with the influx of high tides. The project has been strongly promoted by Prime Minister Silvio Berlusconi, who participated in the foundation ceremony in November 2003. It has met with serious opposition, however, from civic and environmental groups, and it was rejected for financing by the EU commission. The Moses Project does nothing to eliminate the source of the sinking and the industrial exhaustion of the lagoon, and it remains an absurdly expensive technique for saving a city that in so many ways has already lost its capacity to support life. The municipal government, which is opposed to the project, has decided simply to raise the major embankments half a meter to the level of the flooding.

The real death of Venice, however, is not due to calamities of nature and industry, but to the city's success as a place of beauty and desire within a globalized leisure culture. When one travels to Venice, it stimulates an enchanted reminder of what the city was like before automobiles, and it is difficult not to get caught up in the myth of civic life represented by piazzas, bridges, churches, and palaces. One leaves the mainland behind to appreciate La Serenissima's slowed down pace. It is also evident, however, that we are not alone in our visit, and that the city's economy can only survive by becoming a postcard of its past glory. While during the past 30 years Venice's population has declined from 170,000 to less than 65,000, masses of tourists have invaded the floating city, reaching the current staggering figure of 14 million per year. Although the carnival has been revived in the name of civic ritual, it in fact has become part of the exploitational culture of globalization. Citizens can no longer maintain their identity amid such hordes of revelers. The commodification of the image of Venice has made it one of the most sought-after tourist sites but has at the same time completely alienated its remaining inhabitants, who gradually are becoming more or less like the tourists themselves. Although most of its fabric is still genuine, the city is quickly becoming a representation of itself with no life other than tourism.

Françoise Choay caused some controversy a few years ago when she suggested that a facsimile of Venice should be built somewhere else for tourists so that the real Venice could continue its life undisturbed. There are many copies of Venice, the most recent a gambling casino in Las Vegas called The Venetian, which provoked the previous mayor of Venice, Massimo Cacciari, to wonder how he could patent the city to protect it. One of the replicas of Venice that is the most charming is in the theme park called «Italia in Miniatura» in the suburbs of Rimini (about two hours south of Venice). Perfect replicas of Venetian palaces at 5/8ths scale, modeled in silicon, have been arranged like stage sets along a 40-centimeter deep Grand Canal. A soundtrack supplies the calls of seagulls and voices from the windows. The seven-minute boat ride ends with a visit to a mini-Piazza San Marco (missing the famous pigeons), and while it does not permit the same sort of intimacy with real urban life, it is better maintained and managed than today's real version. Nothing can replace the experience of the authentic Venice, but when the authentic starts to become a simulation of itself, the endless reproduction of an image, the experience of «Italia in Miniatura» may not be that different. Choay observed that the appreciation of the facsimile of the Caves of Lascaux was equal or perhaps greater than that of the real caves nearby which have been closed to the general public. While this may be true, the complexity of a city like Venice is in fact not duplicable. No matter how full of tourists it has become, one will always find the grain of civic truth in its piecemeal fabric. In the meantime there is no productive work left in the city, and no matter how authentic its buildings and monuments might be, Venice will never be able to retain urban life without an employment base.

Since the heat wave of last summer, the question of survival has become more than a casual topic of conversation. It is not only cities that will die but the biological life in them. The noticeable climate changes of the last 20 years, and of the last century, seem to indicate the irreversible onslaught of global warming. The greatest production of heat in this age of accelerated entropy in fact derives from urbanization. Cities like Curitiba, Portland, Freiburg, and Barcelona, have made notable advances in confronting their ecological problems at a regional level, while dealing with the distribution of resources at a more local scale. But it will require the development of these exceptional programs for transportation, centralized heating and cooling, bike paths, solar energy, and nature protection on a global level to make a difference in the balance of greenhouse gases. Suffice it to say that most of the world is not doing enough to make a difference. My country, which consumes over 30% of the world's resources with only 6% of its population, has been living beyond it means in terms of the ecological footprint per person—and other countries are hoping to arrive at the same level of well-being, not to mention the billion inhabitants of China. There is no doubt that the race against the human influences on climate change is being lost.

Thus the survival of urban life depends not so much on maintaining any particular form of a city, as it does on the ability to create relationships of responsibility for the use of resources in an urban territory. Three criteria always return for me in terms of the survival of urban life: 1) treating infrastructure as art, meaning its conversion into a social and aesthetic resource; 2) compensating nature with every act of urban intervention; and 3) crossing programs to guarantee the anthropological equivalent of biodiversity. Civic consciousness, the sort that used to thrive in piazzas, needs to find its place in the contemporary urban world, not in a Piazza San Marco flooded with acqua alta and tourists, but in a context more like the one we are using here, that may be more indifferent or even virtual. The city is dead, and we must continue to honor its memory, so that urban life may survive.