The Underground City of Orvieto
The city of Orvieto stands on the summit of a vast volcanic outcrop composed of tuff and pozzolana. Any visitor cannot help but be captivated by this plateau, known simply as “la Rupe”, which rises majestically above and dominates the surrounding valley — a mosaic of woodlands and vineyards.
On this rocky ground, humankind not only found a place to settle and build, eventually raising its cathedral and towers, but also, in every era, excavated underground spaces. For centuries, the tuff has concealed a city beneath the city: Orvieto Underground. The city can in fact be explored deep within its rocky foundations, thanks to a heritage of hypogean spaces unique in the world. A survey carried out in the 1960s by the local speleological group identified a complex of around 1,200 cavities of extraordinary beauty, located not far from Piazza del Duomo: tunnels, wells, silos, dovecotes, kilns and medieval refuse pits.
Here, a remarkable symbiosis between the people of Orvieto and the rock becomes evident: human ingenuity, the demands of everyday life and nature intertwine, forming an alliance that continues to astonish to this day.
Today, these spaces can be visited in the company of highly trained guides, who lead visitors on a journey that feels more like travelling backwards through time than a simple walk through a series of caves. This is the Orvieto Underground experience, a unique and unrepeatable route that, year after year, continues to attract an ever-growing audience, curious and eager to be captivated by new forms of experiential tourism.
The Mill of Santa Chiara
The large millstones belong to an ancient olive press of medieval origin, which remained in operation until 1697, as attested by the date carved into one of the basalt millstones. As early as the 1st century AD, Plinio the Elder wrote that Orvieto’s millstones were renowned throughout the Mediterranean. The oil was extracted using wooden presses, and nearby several ancillary spaces were carved out, including a cellar and a feeding trough.
The Pozzolana Quarry and the Etruscan Well
A vast chamber was excavated for the extraction of pozzolana, a grey, highly friable volcanic material which, when ground into powder and mixed with sand, water and lime, becomes a cementitious mortar. The marks left by the small hammers used to remove cubic metres of rock entirely by hand are still clearly visible on the walls.
An iron railing now borders a vertical shaft measuring 120 by 80 centimetres, which cuts through the entire rock mass to reach the groundwater. This shaft was dug in the 6th century BC by the Etruscans of Velzna, who also left the small niches visible along the walls of the well, the pedarole, used to climb up and down without ropes or ladders.
The Dovecotes
Many interpretations have been proposed for these spaces, ranging from Etruscan necropolises for cremated remains to rooms used for food storage. In reality, they are dovecotes: structures designed for breeding pigeons for food. Each niche provided nesting space for a pair of birds, while the basins used to collect water were essential both for drinking and for freeing the animals from parasites.
On the rear wall, a tunnel is also visible, which once formed a connection with the city above. Historical sources report that in 1632 Pope Urban VIII forbade the people of Orvieto from excavating new caves, including dovecotes, near the edge of the Rupe, for defensive reasons.
The Air-Raid Shelter
One of the easternmost chambers features a bench running along three walls and at least two connecting tunnels. This is one of the many air-raid shelters dating from the Second World War, designed with separate entrances and exits.
Orvieto was a relatively fortunate city, thanks to the combined actions of three decisive figures: Bishop Francesco Pieri, Colonel Alfred Lersen, commander of the German garrison, and Major Richard Heseltine, leader of the British liberation forces.
As Allied troops advanced, the risk of bombing became increasingly real. On 14 June 1944, Colonel Lersen wrote a letter to the Allies, asking them to consider Orvieto an “open city, open to occupation by the enemy” without combat, in order to avoid the destruction of sites of particular historical and cultural importance.
On the southern edge of the Orvieto Rupe, near Piazza del Duomo, lies the entrance to the underground complex known in the 14th century as the Mill of Santa Chiara and today called Orvieto Underground. The first space encountered is indeed a mill, more precisely, an olive press, certainly in operation in the 17th century and, according to documents, probably built in the late Middle Ages.
But why carve an olive press into the rock? Underground spaces served very specific purposes, designed to improve life above ground: this was where oil for the entire city was produced. Original tools are still visible, such as the press, recently faithfully reconstructed, and the olive millstones, with their large, heavy basalt wheels. The visit then continues into the subsequent chambers, which extend ever deeper into the rock.
