The Italian summer proves to be demanding, with heat, humidity and the repeated heat waves that keep thermometers from dropping even at night. There are many ways to try to escape the scorching heat, but one of the most interesting, underrated and fascinating, is the discovery of the underground world: beneath our feet, hidden in the rock of the Apennines and the Alps, there exists an alternate, cool and quiet universe where the temperature never changes, whether January or the hottest Ferragosto. A kind of Upside-Down that recalls Stranger Things, but without monsters, strange clouds and eerie reddish flashes.
Indeed, in the Italian tourist caves, underground cavities carved in millions of years by water and time, one ventures into a world that is at once bizarre and incredibly attractive. Between walkways, lighting and expert guides, one moves among stalactites, stalagmites and subterranean halls that resemble buildings designed by mad architects. A cave excursion, in short, combines a certain degree of climatic relief with geometric and natural wonder, and, in some cases, historical: many of these caverns hold prehistoric remains, underground lakes and concretions that formed drop by drop over geological eras.
Frasassi Caves
Undoubtedly, the Frasassi Caves are the most famous complex in Italy. The reason is simple: they are regarded as the largest underground complex in Europe, with more than twenty kilometers of cavities uncovered only in 1971. They are located in the municipality of Genga, in the Marche region, between the Apennine foothills and the valley of the Sentino river.
Every year they are visited by a large number of people. The classic tourist route, undertaken by the majority of visitors, is about one and a half kilometers long and is completed in just over an hour, following the explanations and storytelling of a dedicated guide. Here the temperature is constant: 14 degrees, with humidity near 100%.
The visit opens with the Ancona Abyss Hall, a space so vast that, according to estimates, it could contain the Milan Cathedral: 180 meters long, 120 meters wide and 200 meters high, dominated by the imposing stalagmites known as the Giants. This is one of the key spaces of the route, a veritable underground cathedral. Other places on the tour include Hall 200, the Grand Canyon (a basin carved by the Sentino river), the slender Organ Pipes and the Hall of Candles, up to the evocative Hall of the Infinite, also called Hall of the Haystacks because it features large conical stalagmites that resemble haycocks.
If you book in advance, you can also choose the longer routes, called Blue and Red, two and three hours long respectively: a more demanding visit to the Frasassi Caves, but one that leads to greater awareness and a more complete discovery of this sensational complex.
Castellana Caves
Castellana, 40 kilometers from Bari, in the inland of Puglia: that ground opening which had long served as a kind of natural dump would become something more starting from the distant January 23, 1938. The speleologist Franco Anelli lowered himself into the sinkhole, discovering what would later become known as one of Europe’s most spectacular karst systems.
Today the Castellana Caves are famous and frequented, one of the most popular alternative attractions to the sea in Puglia. Their great beauty is, of course, the reason, but the fact that the internal temperature remains between 14 and 18 degrees, while the surface temperature in summer routinely tops 30 degrees, is surely another incentive.
The tour of the complex always begins from the Grave, the first and broadest cavern, about sixty meters high and the only point of the route where natural light filters through an opening in the vault. This was the cave into which Anelli descended at the end of the 1930s. From here, visitors can choose between a short itinerary, about one kilometer long and lasting around 50 minutes, or the full route, which stretches for three kilometers and takes about two hours, crossing caverns with evocative names such as the Civetta, the Precipizio and the Corridoio del Deserto. The grand finale is the Grotta Bianca, the last and most famous cavern of the system, covered with alabaster concretions so white they are considered among the most splendid in the world.
Giant Cave
Nomen omen, as the ancients said. And indeed there is no name more instructive than Giant Cave to describe the tourist cave with the largest natural hall in the world. A cavern enormous, located at the border between Italy and Slovenia, in the Trieste Karst. It is located, precisely, in Sgonico, just north of the Giulian capital.
The main chamber measures 98.5 meters in height, 167.6 meters in length and 76.3 meters in width, for a volume of about 365,000 cubic meters: enough, according to calculations, to contain the entire Basilica of Saint Peter. From the early 20th century, the Giant Cave has been frequented by tourists, while exploration dates back to 1840.
The current tourist route runs for 850 meters and goes down to about 100 meters below the surface, along a demanding staircase of 500 steps protected by handrails and anti-slip surfaces, then ascends along the scenic “Carlo Finocchiaro” path to a viewpoint suspended 95 meters above the main cavern. The internal temperature remains fixed at 11 degrees year-round.
Exceptional stalagmite formations, such as the Ruggero Column and the Palma, are remarkable. On the other hand, the origins of the underground complex are traced back to about ten million years ago. The cave, besides being a tourist destination, is also an active scientific laboratory: it hosts the longest geodetic pendulums in the world, used to monitor movements of the Earth’s crust.
Toirano Caves
When it was said at the outset that inside caves one can find traces of history as well as the beauty of nature, the Toirano Caves were the principal reference. In this complex, between 1950 and the following years, numerous remains of the cave bear (Ursus spelaeus) were found, which for millennia sought refuge here during hibernation, evidenced by bones, paw prints and scratches on the walls. But not only: in the cave known as the Corridor of the Imprints, traces left by prehistoric humans about 12,000 years ago were imprinted in the clay: footprints of feet, hands and knees that allow us to imagine the passage of our ancestors through these same tunnels.
The Basura Cave and the Corridor of the Imprints are the two most interesting halls of the route, but the tourist itinerary also allows exploring the Bear Cemetery, a vast repository of bones dating back to as much as 27,000 years ago, and the Antro di Cibele, unique in the world for its concretions. The entire accessible route measures about 1,300 meters and is completed in just over an hour with a guided visit. Inside the caves the temperature remains constantly around 16 degrees.
The Toirano Caves are located near the town of Toirano, inland in Liguria, in the Ligurian region, on the hills behind Loano and Borghetto Santo Spirito, in the province of Savona.
Wind Cave
The Wind Cave is situated near Fornovolasco, a small mountain village in the Garfagnana area of northern Tuscany, at the foot of the peaks of the Apuan Alps. It earns its name from the strong air currents that cross it, generated by the temperature difference between inside and outside; one can literally feel them as soon as the door is opened, with gusts that, according to measurements, can exceed 40 km/h.
Inside the temperature is quite cold, below 11 degrees (to be precise, it remains stable at 10.7 degrees all year round), but with a humidity level approaching 99%.
A fundamental convenience of the Wind Cave is the possibility to choose among three guided itineraries of increasing length and duration, from one to three hours, allowing each visitor to tailor the visit to the time available and their curiosity. The first, shortest, passes through narrow corridors and crystal lagoons rich with stalactites and stalagmites still growing; the second descends into the Baratro dei Giganti to reach a small underground river and the evocative Hall of Voices, where the unique acoustics create surprising effects; the third, the most complete, extends to the deepest sections of the karst system, explored since the end of the nineteenth century and still the subject of study by speleologists. You indeed visit a deep 90-meter shaft, perfectly vertical, which is then ascended to reach a vast hall characterized by beautiful concretions and, immediately afterward, a short underground canyon.
