San Vito is a village that civilisation has left behind. Perched on the verdant foothills of Mount Vesuvius, outside Naples, it appears as a random cluster of concrete buildings - some completed, some not - that stretch out in straggly lines along a series of rutted hillside tracks. Its rubbish sits uncollected in the fetid heat, and its sewage festers in cesspits that slowly bleed their poisons into the surrounding fields. There is no piazza, no church, no recognisable mark of a civic centre. There are no signposts to point you there, and nothing to let you know you have arrived. Instead of vegetation, there are only weeds, cigarette butts and broken beer bottles.
Almost everything about San Vito is illegal, from the houses built without permission, to the cars with out-of-town number plates that suggest either an implausibly high number of visiting relatives or, more likely, a thriving trade in stolen vehicles. Bosses from the Camorra, the Neapolitan version of the Mafia, make little secret of their presence, in well-appointed villas protected by electronic security gates and surveillance cameras. A uniformed official is a rare sight; the police, even when called out for a burglary or an assault, turn up late or not at all.
But San Vito is more than just a mockery of civic authority. It is a disaster waiting to happen. If Vesuvius should erupt again - and sooner or later it will - the whole tangle of concrete and detritus is likely to be buried or swept away, along with dozens of similar communities that have grown up with reckless abandon on the slopes of the volcano.
Because of a near-total absence of urban planning, a wanton disregard for the environment, an acute housing shortage and an orgy of illegal speculative building over the past 30 years, some 570,000 people now living in the narrow strip of land between Vesuvius and the Bay of Naples risk having their houses, if not their lives, wiped out by molten lava and volcanic ash.
The catastrophe, when it comes, will be twofold: the trauma of the eruption itself, of course, and the man-made disaster that will surely follow.
As the citizens of San Vito and the other hillside communities make their escape towards the coastal plain, they will be running into one of the densest, most heavily congested urban agglomerations in the world. The only viable escape route is the four-lane motorway that runs from Naples to Salerno, past the ancient ghost towns of Herculaneum and Pompeii. This road is packed at the best of times and can only be reached by tiny, tightly curved access ramps obstructed by toll booths. One only has to make the analogy of a rush of blood through a single, dangerously sclerotic artery to understand the inevitable outcome: total systemic breakdown.
"When Vesuvius erupts it will be cataclysmic," predicts Pietro Craveri, a professor at the University of Naples. "We're talking about the densest urban area in Europe, comparable only to Cairo or Calcutta. This is a time-bomb just waiting to go off."
Disaster is firmly inscribed on the minds of the four million-odd people who live in the Naples area. A month ago, a cloudburst of early summer rain brought rivers of mud crashing down from the hills 15 miles inland from Vesuvius. Two towns, Sarno and Quindici, were deluged as the mudslides consumed streets, houses and bridges. More than 160 bodies have been recovered, and several more remain unaccounted for. But this is not the worst that Naples has had to endure, or is likely to face again in the future.
There have been countless smaller landslides in recent years, plus a handful of earthquakes, including the shockingly powerful tremor that brought half of southern Italy to its knees in 1980. The pattern of these disasters is always depressingly familiar: a freak of nature compounded by the irresponsibility of a local government that is either corrupt or non-existent, by erosion of the environment through industrial exploitation, deforestation and pollution, and - more often than not - by the consequences of an uncontrolled rash of illegal building.
The recent mudslides are a case in point. The hills above Sarno and Quindici, which were once farmed intensively, have now been abandoned; trees and shrubs have withered and died, and dry stone walls and terraced cultivation have disappeared, making the ground loose and prone to severe erosion. It certainly does not help that much of the groundwater is pumped for consumption across southern Italy, nor that the river Sarno is polluted with effluent from a tanning factory.
The Naples area as a whole is an extraordinary mixture of awesome natural wonders and human abuse, of beauty and catastrophe. Not only is there the looming presence of Vesuvius to the east, but also volcanic activity to the west around Pozzuoli, where the land periodically rises and falls under the pressure of subterranean gases.
The city of Naples itself is ringed by vertiginously steep hills that have been covered by a labyrinth of asphalt and low-grade housing, much of it the result of corrupt land deals or illegal construction. Landslides are a constant fear. In many places, the ground forms a thin layer of tufaceous rock above a network of vast underground caverns. The combination of poorly applied cement, inefficient drains and open sewers sometimes cause the ground to give way altogether and suck a sliver of urban confusion into the depths.
In the old days Neapolitans put their faith in their quixotic patron saint, San Gennaro, to ward off the worst of these ills. The saint is still venerated in a thrice-yearly ceremony at the Cathedral in which a phial of his blood mysteriously turns liquid as a sign of his continuing protection.
But most people, particularly the younger generation, have put such fatalistic superstition to one side in favour of more materialistic solutions to their problems. For a population that until a generation or two ago was still eking a miserable living from the land, owning property remains the key priority.
The first outbreak of illegal building came after the war, and was accompanied by a particularly virulent collusion between building speculators and corrupt local politicians that was famously denounced by Francesco Rosi in his film Le Mani sulla Citta. A half-hearted attempt at regulation came in 1972, but the result was merely to drive what few official building projects there were out of the market and leave the field open to illegal speculators backed by the Camorra. Over the next 20 years, the hills, the coastline and the formerly modest towns beneath Vesuvius turned into an unbroken field of concrete.
Ancient Pompeii, which should have served as a stern reminder of the dangers of building under the volcano, was blocked in on all sides by its modern namesake. Ancient Herculaneum was virtually swallowed up by the new settlement, Ercolano, and is now invisible either from the railway line above or the seafront below. In some cases the builders obtained a token license from the city, usually to build an outhouse or a shed that was then expanded into a cluster of houses or a tower block. But most of the time they didn't bother.
In the words of the city planning expert Roberto Gianni, the local political authorities showed nothing but "neglect, if not scorn" for the rape of one of the most beautiful bays in Europe. "Construction was the engine driving the whole Neapolitan economy. The only way people understood the term "planning" was as a licence to keep building more," Gianni said.
There were more reasonable periods, such as the Communist administration of 1975-83 which succeeded in knocking down a few hundred illegal buildings and impounding thousands more; but these operations were bitterly opposed by public opinion, the media and even the courts. The Left tried to draw a distinction between illegal housing built out of need and the venal speculations of property developers; the distinction did not really exist, though, and was largely a symptom of the political class's subjugation to the construction magnates.
Modern Naples is little short of a basket case. It has the highest birth rate and the highest population growth in Italy; its population density is 15 times the national average. Traffic moves more slowly (10 mph) than anywhere else in the country. Astonishingly, only 26 per cent of Naples province is connected to a proper sewage system. Of 3,300 criminal proceedings currently in progress in Italy for crimes against the environment, 90 per cent are in the Campania region around Naples. Up in Chiaiano and Camaldoli, in an area that was all wooded rolling hills until the 1970s, the sewage flows through natural river beds and seeps into houses.
Many of the chestnut trees that stood proudly upon Naples' highest hill have been infected and died. Much of the area has been used as a quarry for tufa, the soft yellow rock on which Naples is built. Some of the quarries in the area are a hundred metres deep, driving a series of alarming sheer wedges into the natural landscape. They are all illegal, but that did not stop the city council from using tufa from these quarries to restore the Royal Palace for the G7 meeting held in Naples in 1994.
Some effort has been made to preserve the geological integrity of Camaldoli hill by opening a city park at its summit. But the park is unmanned apart from two middle-aged men on work experience schemes. Much of it has been closed off for lack of maintenance; the chestnut trees have not been pruned in years and are drying out and dying. The chances are high that one day part of the hillside will simply come away, drowning the suburbs of Pianura and Soccavo below in mud and rock.
What can be done to avert such disasters? Precious little in the short term. The good news is that illegal building has come to a standstill since the collapse of the old political order under a sea of corruption scandals, and the election of an energetic left-wing city council in 1993. There has even been a return to agricultural land use on a modest scale. But the bad news is that the problems of illegal house and environmental blight are too huge for any city government to tackle within a reasonable time-span. Roberto Gianni, who is now chief town planner, has ambitions to create a green belt of countryside on the hills above the city. The head of Chiaiano district, a young architect called Agostino Di Lorenzo, wants to turn one of the tufa quarries into an open-air theatre.
Across Naples, the strategy is to look at illegal projects that could feasibly be turned into full-blown housing developments and offset them by identifying buildings that need to be knocked down for environmental or security reasons. That way urbanisation can be contained and the city can gradually breathe again.
The problem is that this strategy cannot work beneath Vesuvius, where population density is so great that there is no room left for manoeuvre. The only way to shift people and make room for parks and proper roads would be build further up the mountain, which is not an option. The city of Torre Annunziata has not even closed its absurdly positioned hospital, which lies at the point where one of the main lava flows from Vesuvius would flow into the sea in the event of an eruption.
A few hundred yards uphill, the people of San Vito see little reason to put any faith in the state. "When the moment comes, nobody will come to save us," lamented one resident, a middle-aged man who wanted to be known as Gennaro. He gestured vaguely towards the Camorra compound a few hundred yards from his house. "This is a place where the strong get ahead, not those who follow the rules. We're afraid of a lot of things besides the volcano."
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