Naples:life,death &
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entry Oct 2013


Coastal Caves in the Flegrean Area
What follows is a summary of information contained in a report by Raffaella Lamagna and Graziano Ferrari entitled Coastal Caves in the Phlaegrean Area. It was done in 2006 and was followed in 2007 by a second report of preliminary findings. These studies were commissioned by the Regional Park of the Campi Flegrei (the Phlaegrean Fields; the English spelling 'Flegrean' is now common and is the one I use here except when citing the title of the studies). The Flegrean areas that make up the regional park are not contiguous but are actually separate sites in the Neapolitan suburbs of Bagnoli, Posillipo, Nisida, and Agnano, and in the adjacent towns of Bacoli, Monte di Procida, and Pozzuoli. In all, there are about 3,000 hectares (30 sq. km or 11 sq. miles) defined as protected areas, marine reserves, Sites of Community Interest or Zones of Special Protection. The Coastal Caves are one such area of special interest. The photos (permission pending) in this entry are all from the 2007 report of preliminary findings. Some of the text, below, is cited from the authors' English version of their Italian text.
The Grotta del Tuono (Thunder Grotto) on the    
Posillipo coast, seen by the light at sunset       
Coastal caves (submerged, littoral, or dry) are found all along the Italian coastline. Generally speaking they may all be said to be of environmental and scientific values. However, it is also true that they are sorely understudied and, thus, governmental agencies and park services have little chance to enforce proper protection towards a sustainable use of the caves. In particular, the Flegrean Fields have a large number of coastal caves (approximately 200). They may be tiny or huge, natural or man-made, and they extend from Torregaveta in the west just past Monte di Procida (the promontory that marks one end of the Gulf of Naples) eastward to Mergellina, the small harbor just before you get into the “real city” of Naples. That is a coastline of about 30 km/20 miles. The caves have been places of important biological research since the 1700s. In comparison with other coastal cave areas, the Flegrean Fields have a special quality in that many of them combine both natural and historical points of interest. Indeed, many caves are not natural, but were dug in the soft limestone tuff by the Romans to get building material for imperial and aristocratic villas or to build service structures for the harbors used by the Western Imperial fleet.

Due to earth movements caused by quakes and smaller (but important) movements* several caves are now half filled with sea water; they are an example of a very specialized and vulnerable habitat, useful as environmental quality indicators. Generally speaking, caves are conservative environments, as they preserve traces of past eras and climates, quickly lost on the surface. In particular, artificial coastal caves can provide information about the relationship between submerged ancient structures under investigation, and land structures, now obliterated by recent urbanization.

*These smaller movements are called bradiseisms and, by definition, are gradual movements caused by the filling or emptying of an underground magma chamber and/or hydrothermal activity. The Flegrean Briadiseism is of such interest that it is now a proposed new site for inclusion on the UNESCO World Heritage list (see this off-site link).

This image is one of many from the
second report that locate the caves
(the red dots) with precision. The text
contains descriptions of many of the caves.



In spite of general interest over the last few centuries, the Flegrean caves have gone largely unstudied, at least in a rigorous scientific sense. Certainly, application of the multidisciplinary resources available to modern archaeology, geology and marine biology have been neglected. This means that the coastal caves have not fulfilled their potential to advance cultural and scientific knowledge, or even their potential for tourism. In order to avoid further risk to these important scientific and cultural resources, the Province of Naples, Department of Agriculture, Parks and Civil Defense and the Flegrean Fields Regional Park have proposed a plan that would

(1) collect a specific bibliography on the coastal caves;
(2) collect historical documentation such as photographs, maps and surveys;
(3) identify and accurately map the location of coastal caves;
(4) photograph the caves as they are at present;
(5) make a detailed study of the caves most relevant in terms of geology, biology, and archaeology.


Ancient caves along the shoreline of old Pozzuoli


The authors of Coastal Caves in the Phlaegrean Area, Lamagna and Ferrari, cite these works as references:

-Cavolini Filippo, 1785. Memorie per servire alla storia de’ Polipi marini. Napoli.
-Cicogna Fabio, Carlo Nike Bianchi, Graziano Ferrari & Paolo Forti (Eds.), 2003. Grotte marine: cinquant'anni di ricerca in Italia. Ministero dell’Ambiente e della Tutela del Territorio.
-Federazione Speleologica Campana, 2005. Grotte e speleologia della Campania. Atlante delle cavità naturali. Elio Sellino Editore, Avellino.


The authors' second report is a major step in cataloging and documenting the coastal caves. They added in this second paper the area of Pizzofalcone, the height overlooking the sea and the site of the original city of Parthenope. My understanding is that this is an open-ended project. It is certainly a treasure for future researchers.


[Also see this related entry on the coastal caves of the Cilento.]


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