A piece of the adventure experienced by a small group of speleologists in the eighties, at the thrilling re-discovery of the 1200 grottoes of Orvieto.

Once upon a time there was… a city. It’s like the beginning of a fairy tale; instead, it’s the beginning of a story that, just like an old fairy tell, tells of an almost incredible adventure: the discovery of a city under a city.

The city is Orvieto, which already looks as though it has come out of the pictures of a story book, perched as it is on a high Rupe, its peripheral verticality isolating it from the rest of the world. A Rupe that, though it has supported the city for three thousand years, still proves to be inexperienced in performing a task of such great renown: collapses, landslides, falls and tremors have always made its inhabitants suspicious. To blame is the fragility of the rocks forming it: tuff and pozzolana. Extremely friable materials that can almost be scratched away by fingernails. But it’s for this very reason they are materials that can easily be dug, perforated, to open a grotto… two… one hundred… a thousand.

The story is that of the adventure of several speleologists who, beneath the small historic centre of Orvieto, right inside the big Rupe, so prone to instability, found an incredible underground world that had been dug, used and then forgotten: a dark labyrinth subdivided into over 1200 grottoes, tunnels, wells and reservoirs, created by man, blow after blow with a pickaxe, in almost three millenniums of persistent and continuous work.

It all began at the end of the seventies, when a great landslide made a big bite into Orvieto’s Rupe, a few hundred metres from its very famous Duomo. The last, and most serious, event caused by the hydrogeological disruption that threatened the stability of the Rupe, the landslide alarmed the whole world, worried about the survival of Orvieto and its works of art. But it intrigued the small and experienced group of local speleologists, already alert to a sort of urban legend which, certainly by emphasising fragments of a reality that local historical memory could no longer remember coherently, mythicised an Orvieto “all empty, beneath”. The same Rupe revealed, in some of its high and projecting walls, mysterious gaps, windows with irregular contours, empty and dark eyes that hinted at an inexplicable and unexplored underground world and which, like cosmic black holes, were a source of irresistible attraction for Orvieto’s speleologists.

The discovery of the incredible underground reality began with these very elevated holes. After securing ropes to trees in the gardens that crown almost the whole of the city’s upper perimeter (and, where there aren’t any trees, they were secured to the axle shafts of cars), the speleologists began to let themselves down the many-sided Rupe. Thrill. Thrill is what can define, in one word, the resulting sensations that characterised their explorations. Thrill, first of all, at the open spaces in which the descents took place: the speleologists were accustomed, yes, to fearlessly using ropes to cover great heights but in the narrow atmosphere of the grottoes where vision was limited to the bit of space stolen by the acetylene from the darkness and the darkness itself kindly banishes any dizziness. Here, however, they had to get accustomed suddenly to working in the open air, with their eyes free to sweep kilometres and the rope which, in that vastness, was no longer such but only a very fine thread… and anyone who denies feeling trepidation, at least the first few times, is not being truthful. Thrill, above all, for what appeared once they got into the rupestrian grottoes. Square rooms, linked together by galleries and illuminated by small windows, followed in succession for metres on different overlapping levels joined by short wells and chutes. In the back walls, the more internal walls, there were narrow tunnels went through towards the heart of the Rupe and barely allowed a person to pass on all fours or lying down, but only for a few metres because unfailingly a landslide would present irresolvable questions on their destination. The years had covered the floors with a thick layer of very find pozzolana dust; with every step it would fly up, remain suspended in the still air, at times ruled by slanting rays of sun falling from the small windows, giving those unique grottoes an aspect that evoked an almost magical atmosphere. But the walls of those rooms, rather than the rest, gave the impression of entering an eerie dimension, into a world that was only a disturbing imitation of the one on the surface: thousands of small cubic niches a few inches deep completely covered them uninterruptedly, from floor to ceiling. An image that called to mind the words that Jorge Luis Borges makes the protagonist of the story “The Immortal” say: “This building is the work of the gods” I thought at first. I explored the uninhabited enclosures and corrected: “The gods who built it are dead”. I noticed its unusualness and said: “The gods who build it were mad”. No god had, of course, worked on that piece of work and, of course, no madman. Everything, however, responded to precise criteria for the rational exploitation of the subsurface. The speleologists had discovered those underground preparations known by the name of “columbarium”, dug by the Orvieto’s ancient people just behind the outside walls of the Rupe to breed, in the small niches created on purpose, pigeons, now a classic dish of the local cuisine.

The insight of the researchers thus began to find proof, confirming the popular rumour that claimed Orvieto was “all empty, beneath”. In fact, the town’s subsurface began to reveal itself and reward the researchers with such a large quantity of grottoes as to make it necessary to carry out, parallel to their exploration work, an accurate task of cataloguing that divided the cavities discovered by type, excavation period and other criteria which made filing the information gathered the logical thing to do. At this point the speleologists were joined by archaeologists and the town continued to reveal its incredible underground recesses, real roots on which the town had grown and stratified and which time had let fall into oblivion. In all, over 1200 grottoes were discovered, but the numerical fact, although astonishing, is nothing however but an arid quantification of the work carried out. It doesn’t relate what one feels, for example, when passing through a narrow tunnel that leads to a well where the beam of an electric torch fades away without finding the bottom. And so down with another rope, and a vertical descent begins in a narrow passage less than a metre in diameter that ends thirty-five metres later on a heap of debris thrown down no one knows when or by whom. Halfway down two tunnels vanish into the darkness. A short plumb line, a unique underground swing to reach and explore them but they end shortly after. The old diggers didn’t continue with their exhausting underground work. Why? There’s no answer. And above, the city goes on with its daily life unaware that right underneath, a few metres down, a researcher armed with a helmet is crawling through a passage opened up by a small collapse, cautiously brushing past unstable and worrying boulders, peeping, after lighting it up again after centuries of darkness, into a cistern and seeing again the yellow glimmer of the acetylene, the big ashlars of tuff skilfully overlapped by the Etruscans in the fifth century before Christ. The joint work by the speleologists and the archaeologists made it possible to rediscover the grottoes beneath Orvieto as well as to systematically and scientifically study the information retrieved.

The Rupe, colonised since the ninth century before Christ then saw an important Etrustcan town prosper, the ancient Velzna. The early hypogea dug by man in search of water date back to this period, water being an irreplaceable resource in a city that, impregnable because of its insuperable walls of rock that protected it, had to be able to resist sieges. Unfortunately, on the high plateau of Orvieto’s Rupe water is completely absent. From this lack rose the need to dig wells. Very deep wells, all are rectangular and don’t measure more than 80cm by 120cm. So narrow, they fall straight down for metres and metres in search of underground springs. The longest two walls are marked, at regular intervals, by small notches, called “pedarole”, which made it possible to move within these vertical channels. And they still make it possible today: the speleologists, after placing the tips of their toes on the footholds, went down and came up again, knowing excitedly that they were repeating, due to an inevitable automatism imposed by the characteristics of the well, actions already repeated a thousand times, exactly in the same place, by other men twenty-five centuries before. The Etruscans also created cisterns for holding rainwater as well as an extended network of tunnels for its conveyance. It suffices to say that thanks to all this, Velzna managed to become self-sufficient as far as its water supply was concerned, so much so that it fell into the hands of Rome, in 264 before Christ, only after withstanding a siege that lasted more than two years. Over successive centuries the digging continued. The subsurface of the city revealed enormous pits from which tonnes of pozzolana were estracted, wells and cisterns of all ages and sizes, galleries, cellars, shelters, litter wells that still provide fragmentary samples of refined medieval and Renaissance ceramics. Sometimes, the discovery of some hypogea of great importance is a necessary gift like, for example, when they found what is now known as “Il Pozzo della Cava”. The owner of a local restaurant in the medieval district noticed that some walling in the restaurant cellar, which seemed to be a mere support job, gave signs of collapsing. After removing a small block of tuff he discovered… a void! Beyond the old wall there was nothing! The speleologists, who promptly arrived as soon as they heard of the discovery, spun metres and metres of rope beyond the small passageway that had been opened and descended into the darkness, not without precautionary squabbles as to priority of descent which were nevertheless gallantly settled with nudges of the elbow. A big well received them holding them on its bed covered with debris, almost thirty metres further down. They also discovered that the wall of the well was marked, all along its height, by the trace of a small well with footholds, typical of the Etruscan period. But the surprises didn’t end there. After several years, the owner decided to clear the debris from the bottom, attracted also by the discovery of documents testifying to the presence of water at least until the XVII century. After digging for a few metres the speleologists found themselves before a small tunnel (at a depth of more than 35 metres!), obstructed after about fifteen metres by a great quantity of clay preventing them from proceeding with exploration, marking a new big question mark on the map of Orvieto’s underground search.

But perhaps the most fascinating discovery was that made in a cavity near Piazza Duomo. There an entire medieval oil press for olives came to light, complete with millstones, press, furnace, mangers for the animals working the grindstones, water mains and cisterns. A big system installed in a grotto that, due to the particular aspect given to it when digging took place, immediately calls to mind the symmetrical patterns of many hypogea of the Etruscan era, suggesting fascinating hypotheses both on the time of their realisation and their former use. A place of great historical and archaeological interest allowing anyone to directly feel the fascinating touch of the past. In fact, every day, starting with the offices of the Tourist Promotion Company in Piazza Duomo, qualified staff accompany visitors on an easy route for about an hour called “Orvieto Underground”, which unwinds through two of the biggest and most important grottoes hidden in the Rupe. Here, in search of the ancient secrets preserved by the silent darkness of the grottoes, everyone can rediscover, to their surprise, the millenary charms of the underground labyrinth.

The characteristics of the rocks outlining the complex stratigraphy of the Rupe on which Orvieto stands, determined the environmental conditions that led its inhabitants to dig underground until they formed the incredible maze of grottoes, wells, cisterns and tunnels that today take the name of Orvieto Underground.

Seen from afar, for example when arriving by motorway or going down the sharp turns of the main road 71 coming from Viterbo, Orvieto has a very particular appearance, immediately intriguing thanks to a remarkable sight. At the southern end of a wide valley enclosed by hills, some of them wooded, some neatly lined by vineyards, it stands out like a relief in perfect isolation, its slopes rising softly from the bottom of the valley. At the top, almost as though planted there by a mythological giant, a vast tuffaceous block with tall and smooth perpendicular walls supports the city which with its roofs, towers, domes and spires, breaks and stirs the fairly level surface of this unexpected plateau called "Rupe".

The stratigraphy of the charming structure is somewhat complex but, starting from the bottom, it can be simplified into the following three layers:

• the hill, formed by Pliocene clays, the old seabed present here before the emergence of the Apennine range;
• the “Albornoz series”, a thin layer not visible everywhere, originating from deposits in a fluvial-lacustrine environment including layers of volcanic origin, so called because it emerges with greater emphasis near the fortification erected in the XIV century by Cardinal Albornoz;
• the actual Rupe formed in the course of about three hundred thousand years from what was the final eruption of the complex volcatno of the Volsini Mountains. It is composed of lithoidal tuff with black scoriae including real yellow-orange tuff, of lithoidal texture with numerous inclusions of pumice, and extremely friable rock of a grey colour that incorrectly takes the name of pozzolana.

This particular stratigraphy influences the circulation of underground waters and observing helps to understand why, over the millenniums, the inhabitants of the Rupe worked so peculiarly in the city’s subsurface, so much that they dug about 1200 grottoes.

Both the tuff and the so-called pozzolana, due to their natural porosity and the large presence of fractures, appear to be completely permeable, which is why the meteoric waters that fall on the Rupe don’t encounter obstacles as they go down to the impermeable layer of Pliocene clay.

This is where the sub-horizontal flow begins giving rise, all around the large tuffaceous block and right at the junction point between the clayey layer and the upper layers, to various springs. Therefore all the water available to the built-up area has always come from outside of here or rather, from outside the vertical walls of the Rupe, always considered by Orvieto’s ancient inhabitants as insurmountable protective walls. It is difficult to imagine how, beyond the difficulties of everyday provisioning, this situation could be extremely dangerous in the event of a siege: it would have been impossible to leave the city and reach the springs now fallen into the hands of the enemies. The unbreakable need for a water supply was therefore the incentive that probably set in motion the realisation of Orvieto’s underground world. Elaborate cisterns were thus dug to hold rainwater and deep wells that, once the permeable layers were overcome, reached the phreatic surfaces.

Along with these hypogea, pertaining purely to seeking and holding water, all the other grottoes were dug too, for a vast range of needs. In this case too the special geological nature of the Rupe came to their aid: the insubstantiality of the pozzolana and the inadequate hardness of the tuff made it possible to make the best use of Orvieto’s subsurface, thus creating that surprising “double” of the city, Orvieto Underground.

A rapid tour to find out where to park, where to walk, what to see in a city that at every turn presents charming and unforgettable views, works of art and unique monuments.

A tourist visit of Orvieto… begins before getting to Orvieto. It seems a paradoxical slogan or the paradox for a slogan but in reality, one starts to enjoy the city from afar, when it appears high on its tuffaceous Rupe. This is the first view that one has: an island without sea dominating a vast plain, a stone ship that, amid the mists (often in the morning), sails visionary seas, a city with a peculiar appearance described as “high and strange” by Fazio of the Huberts in the mid XIV century.

Once beneath the Rupe the problem of parking arises and is immediately resolved. There is a choice between: Funicular car park (very ample), near the railway station, linked to the centre thanks to the characteristic funicular which in approximately two minutes arrives in the city, dropping passengers right opposite the bus stop for Piazza Duomo; Campo Boario underground car park, halfway between the valley and the city, served by elevators and escalators leading to the centre; Piazza Cahen car parks, in via Roma (indoor) and piazza Marconi, inside the city.

For a complete tour of the city, it is worth having at least a day or two at one’s disposal… but, as we all know, time is a hard master.
Of course the Duomo is an unmissable destination, called the Golden Lily of Cathedrals for its mosaics that ornate its incomparable façade, designed at the beginning of the XIV century by Lorenzo Maitani. The interior, rich in works of art, houses among other things the fine marble group of the Pietà, sculpted by Ippolito Scalza in 1579. The artistic jewel in the Duomo is the Chapel of San Brizio on whose walls the artist from Cortona, Luca Signorelli, frescoed (1499-1504) a Universal Judgement which is one of them highest testimonials of Italian painting.

Let us remember that from Piazza Duomo n. 23 right in front of the Cathedral, at the Tourist Information Office, every day of the year, at different times, guided tours depart for "Orvieto Underground".

The lowest point of Orvieto, in piazza Cahen, is where the notorious St. Patrick’s Well is situated. It can be visited right to the bottom thanks to two convenient flights of stairs that sink to about 60 metres inside the hollow of the well itself. It’s a work of incredible engineering, designed by Antonio da Sangallo the Young in 1527 on assignment by Pope Clement VII who sought refuge here to escape the troops of Carlo V who destroyed Rome. The two flights of stairs wind around one another like a double DNA helix, one serves to go down and the other to come back up. The ingenious system made it possible to directly reach the water with pack animals and then go back up without getting in the way of those going down.

Not far from the well is the panoramic Albornoz Fortress (1364), now a public garden, from where the view sweeps across the valley and the hills surrounding the city.

The topographic centre of the city is the medieval Torre del Moro (open to visitors), at the intersection between Corso Cavour and Via del Duomo. From the top, one enjoys a 360° view of the city and its surroundings.

Also in the centre, the Palazzo del Capitano del Popolo can’t fail to amaze, a building dating back to the XIII century, powerful and elegant, adorned with arches, windows with three lights and swallow-tailed merlons. Following careful restoration work that didn’t fail to fully enhance several evocative Etruscan and medieval remains found in the basement rooms, the Palazzo has become a modern conference centre.

The medieval districtv is not far: it occupies the western part of the city. Characteristic and precipitous, it offers an exceptional walk along the banks, down very steep and narrow streets that go back over the old rounds. Among the houses, joined together almost without a break, tall spurs of tuff celebrate every day the indissoluble union of this city with its magical tuffaceous Rupe. It is worth taking one’s time and getting lost among these lanes, enjoying the moment they open up into squares, large and small, and the unexpected wide and green panoramic views.

There are many other surprises that the city can still offer curious travellers: ancient churches that preserve outstanding pictorial or sculptural works (San Francesco, San Domenico, Sant’Andrea, San Giovenale, San Lorenzo de Arari); Renaissance buildings of linear but rich architectures, where grey basalt is set in yellow tuff embellishing it with inserts that are jewels of equilibrium between form, dimension and ornamental elements; underground surprises such as the incredible Orvieto Underground, which makes it easy to visit the traces that almost three millenniums of human work have left in Orvieto’s grottoes or the Pozzo della Cava, a deep cylindrical perforation whose early structure dates back to the Etruscan period.

But in order to get a full picture of Orvieto, a visit is advisable also to its oldest past, to the testimonials of life that the Etruscans led here, founders of the city which at the time had the name of Velzna and was so rich that it was known by the name of Oinarea (where wine flows). The Museo Archeologico Nazionaleand the Museo “Claudio Faina” are there for this purpose, in piazza Duomo itself. Just outside Orvieto, on the other hand, the Necropoli di Crocefisso del Tufo was the city’s cemetery from VI to III centuries before Christ. What is striking is the precise order in which the tombs were aligned, an obvious sign of a sort of urban development plan (!) that established the general plan of the site, as well as the architraves of the entrances to the tombs themselves that “announce” the name of the dead (the wording of the inscription is in fact “I am from…”).