The Costagliola Hill of San Potito
by Clemente Esposito
Via Francesco Saverio Correra winds its way down for 560 meters to connect via Salvator Rosa at 80.5 meters with via Pessina at 39.9 m. That is a 40.6 m drop at a 7.25% gradient. After the Flegrean volcanoes laid down the large tuff mass, the area around via Correra was marked by a deep gash from running water on the surface, truly torrential rain from the upper reaches of Naples, precisely from Arenella. At 80.5 meters those waters branched into two currents, the south fork being via Correra and the north one via Salvator Rosa. Those two branches bound an area of some 80,000 sqm and make up the old “San Potito Hill”, a name still used today in common jargon. From a geological point of view, we see that this hill, essentially made up of yellow Neapolitan tufa, plunges to the east, that is, down towards via Pessina at a slope of 20 degrees. The stratification is as follows: from the surface down to 6 meters we find hetero
Celano (1617-1693), in the middle of the period of the Spanish vice-realm, describes part of Piazza Dante, then called “Piazza Mercatello” (little market), saying, “Once you pass vico Avvocata, there's another street that leads up to the Capuchin monastery. It's called the Cavone because this is where torrents of water flood down from the hills higher up. These waters have now been channeled away and the area has many streets full of comfortable dwellings.” From Celano's description, we see that the word, itself, 'Cavone' [lit. a large cava, that is, cave, hollow] is said to come from the fact that the torrential waters “dug out” [the Italian verb is cavare] this street [via Correra] and that the first settlements began in the 1600s. Yet it seems that the etymology of the word is, in fact, not really what Celano thought it was. The name springs from the activities of man and not from natural phenomena. True, centuries of rain washed away the loose surface soil on top of the tufa roof and gouged into the rock, itself, but that process proved to be optimal for extracting building material not just underground but directly from the surface, where the waters had laid bare the rock. Viceroy (1533-47) Don Pedro di Toledo was aware of that potential but issued an edict that forbade digging up the area to mine rock for construction. That edict supposedly was in effect throughout the period of the vice-realm (1503-1734); yet it seems that it was precisely during those years that a myriad of quarries opened in the Cavone [thus, in this sense, 'large quarry'] not only naming it but actually expanding it, making further settlement possible. That is how real settlement of the area started in the 1600s; other nearby hills started to urbanize at the same time, the so-called age of Costigliola [a family name in the area].
It is clear that the situation at the top of the hill was more pleasant than down at the bottom of the Cavone. Higher elevations were safer and more scenic. Thus, as usual, the more panoramic properties higher up were cornered by the wealthy and by various religious orders. In chronological order: in 1615 the sisters of the order of S. Severo bought the garden and palazzo of Vincenzo Capace, turned it into a cloister and then expanded by buying the home of the marquis of Pretacatella, where today you find the church of San Potito. That settlement still exists and extends from via Pessina to Vico Rose. It is comprised of the church of S. Potito, today closed, and the old convent now taken over by the carabinieri renamed the Salvo D'Acquisto Barracks. In 1617 the fathers of the Clerics Regular Minor, so-called of S. Maria Maggiore, bought a building from Francesco Carafa where they opened a small church. The complex expanded over time; indeed, “...at the church you find a shelter (conservatorio) and a school for young women.” The founder was Francesco Criscuolo in 1825, but it didn't open until 1832 under the name of the Immaculate Conception of Mary and of the Archangel Gabriel. Those premises, too, still exist and extend from vico Rose to the crossing of via Salvatore Tommasi with via S. Monica and the Cavone ramp. The property owners have changed, and it is precisely the conservatorio that was acquired by private parties. The monastery belongs to the city and the church; it is in the form of a Greek cross, has a very high dome redone in the last century, and still bears the name, S. Giuseppe dei Vecchi.
In 1624 some devout Neapolitans founded “a conservatorio for their children”. That shelter with the annexed church of S. Monica, became a cloister in 1646. It is still functioning and is in that part of the hill that runs from the Cavone ramp along all of via S. Maria to via Salvator Rosa. All of these settlements are in the strip between via Salvatore Tommasi and via Francesco Saverio Correra. Further in, between via Tommasi and via Salvator Rosa, we have the church of the Sacramento (1634) on via S. Giuseppe dei Nudi. In 1646 that church became the church of Saints Bernardo and Margherita and today is called the church of St. John of the Sovereign Order of Malta; still on the same street we find (at #76/a) the church of S. Giuseppe dei Nudi from 1706. The first information that we have regarding settlements near the bottom of the hill is vague; it is also from Celano. The information is vague because there are no homes of the nobility in the area or even—rare for the streets of Naples—churches or other religious structures. From this we can infer that here, originally, is where poor people lived or where merchants had storehouses for their wares. There were, in fact, five major warehouses (Fondaco): Cavone, Ragno, S. Potito, S. Monica and San Giuseppe. Historically, the origin of these warehouses is interesting: they were “originally meant as storehouses for foreign merchants or for citizens who could deposit their wares there, at a customs discount, while they sought contracts.” In the course of the centuries the traditional lack of space and housing that has always afflicted Naples led parts of the population simply to move in and take them over as dwellings even thought they had not been designed for such.
http://www.napoliunderground.org/administrator/index.php?option=com_content&view=article&layout=edit&id=254Literature from the 1800s has made some of these buildings famous. They often served as social centers and are always characterized as places of infection and the worst hygenic conditions imaginable. The dwellings are for the most part on the ground floor, and it is here that the misery of Naples is at its most bitter and painful and where life has maintained unchanged its dreariest aspects. It has remained the same from the time of the Spanish viceroys to today, a material poverty that weighs on the people like an ancient curse, counterbalanced by a wealth of sentiment and decency that is the great moral strength of these poor people. And it is precisely here (in the night from Friday to Saturday, March 13, 1982) behind via. F.S. Correra 207 that an entire tuff wall collapsed upon these people; the several tons of hard stone slammed down onto and crushed the two-story building at #207, killing one person. A greater tragedy was avoided beause the inhabitants had been forewarned by a fall of single smaller blocks of stone. The next morning, daylight showed the disaster in its entirety. The collapse affected, directly and indirectly, the area bounded by the buildings on either side of via F. S. Correra #207 as well as those at via Salvatore Tommasi 16 and 19.
This area is spread along the ridge to the right of via Correra and is characterized by an absolute height of 45 meters at the Cavone and 75m at Via Salvatore Tommasi, with a relative vertical drop of 30m. The area is a rectangle, 120m x 45m, i.e. 5400 sqm that contains the two-story building that collapsed and that was then demolished for reasons of safety. Just in this area alone, seven quarries were discovered, and though they were at different levels both in the tufa and looser materials, all fit in the category of surface cavities, one that also includes the rainwater cisterns. All those empty spaces had served exclusively for the extraction of tufa and were independent one from the other. It is thus clear that there is another category of cavity from that of those found at greater depth even if they are of the same type of excavation; most of the time even these empty spaces are hiding as quarries or rainwater cisterns, but they are part of the aqueduct, a network of thousands of cisterns connected by channels extending beneath the entire city. The beginnings of that aqueduct go back to the Greeks, and remains of it have been found on via SS. Apostoli; it was surely perfected by the Romans to channel the waters of the Serino river to Naples in the area of the Ponti Rossi (red bridges). That aqueduct was born with the city and grew with it; and a city beneath a city is subject to the same stresses as the city on the surface. For more than 20 centuries, they have expanded together, and today, as you move along the hidden city you read true pages of history, or graffiti carved directly into the walls. A subsoil that has served the city for 2500 years cannot have secrets—nor should it, being a copy of the city on the surface, ordely where the surface is ordely, chaotic where the surface displays its urbanized disorder, and dangerous where the surface has suffered unauthorized development and expansion.
The subsoil follows the development of the city, and since we have said that the settlement of the area in question goes back to around 1600, it follows that the aqueduct that services that zone must stemfrom that same date. Thus we can fix the date of the Carmignano aqueduct; it started in 1629. That is not a feat of logic. Quite simply they have found a well at via Tommasi 16 that bears a marble plaque inscribed with “Carmignano Aqueduct.” With all the work that was to be done in the area of the collapse to let families back to their homes and possessions, the only job they managed to get done—one which was not sanctioned by any technicians from the city government—was to fill up the holes from the collapse with cement. Thus they obliterated the only documented case of quarry collapse we have had. To say that the area around the museum is chaotic is an understatement. It has for years been an urban nightmare with no easy resolution, whether you're talking about the various urban environments that have just grown up in the area, the traffic, the lack of green spaces, or the simple population density—one of the highest in Naples (39,000 inhabitants per square kilometer). It is clear that things proceed underground in a more or less parallel fashion. The area is serviced by various main channels that run along at different levels and are from different epochs even though they are all part of the same large vascular system. As you might imagine, that will have its consequnces.
At the end of the 1800s the aqueduct was still in service but was little by little being phased out as the city went over to high-pressure water lines started in 1885 by an Italian-English company. At the time Melisburgo wrote about the area, called “Quartiere degli Studi” (University Quarter), that to supply the quarter with water, the water would have to be brought to the surface a number of times since it couldn't move underground from one conduit to another. We are in somewhat the same position after 40 years of trying to complete a survey of the cavities that exist beneath Naples, particularly in that area. Surely we are not luckier than Melisurgo who had to deal with the problem of the difference in levels of the various conduits, but had 400 open wells with which to access the subsoil.
For the most part these 400 wells are blocked today because they have been used as dumps; thus, it gets more and more difficult and even impossible with the passage of time, to draw a complete picture of that aqueduct system. We know for sure that the part that serviced the area where the collapse took place belonged to what was called the “Azzolino” canal, which ran off of the main canal called “Formale Reale”, which ran a few meters higher up and parallel to via Pessina; this explains all the interruptions due to flooded tunnels as we tried to complete a survey of that area. In the area of the collapse we found two unobstructed, one at via Correra 207, the other at via Tommasi 16. At the first one there were two cisterns of the Carmignano aqueduct; at the second there was one. Unfortunately, flooded tunnels kept us from investigating further.
All published content, unless otherwise indicated, is subject to the Creative Commons license
The site www.napoliunderground.org is updated irregularly and thus is not to be considered a newspaper or editorial product as defined by law n.62 of March 7, 2001
Napoli Underground (NUg) is an independent organization concerned solely with exploring, researching, educating and informing; it is not connected with any of the many associations that serve tourism and/or provide guided tours of our city.
View e-Privacy Directive Documents