1- Green Cave of Pradis
The conformation of the soil of karst origin and the corrosive action of the water carried by the Cosa stream have produced a spectacular natural representation in the municipality of Clauzetto (PN). The green caves were first explored in the mid-1900s but were once a refuge for prehistoric men and animals. Inside, in fact, numerous fossils have been found, finds of flint and pottery shards. The ravine is a canyon with rough and steep walls, created by the erosive force of the stream. It was named after Don Giacomo Bianchini who in 1921 wrote a poem highlighting the beauty of the place and anticipating future development.
The largest of the three cavities is the Grotta della Madonna, a large hall that has been used as a space for liturgical celebrations. In 1968 the cave was called the National Temple of Speleologists and since then, celebrations have been held every year that attract numerous participants. In the adjoining cave there is a refreshment point operating mainly during the summer season. Going down 207 steps you reach the bottom of the ravine and through a bridge you reach a crucifix build by the M.ra Gatto of Treviso.
In the surrounding area, the waterfall created by the waters of the Rio Mola can be reached through bridges and observe the ravine, a narrow and steep gorge due to erosion on the bottom of which a stream flows.
2- New Cave of Villanova
The Alta Val Torre is a treasure chest that contains gems of rare beauty from a naturalistic and speleological point of view. Like a sculptor who models clay, water has patiently created in millions of year, in the darkness and silence of the heart of the earth, the true wonders that we can admire here: the caves Villanova delle Grotte, a beautiful village called "the balcony on the Alta Val Torre" for its panoramic position, has a real karst complex in its subsoil. The "queen" of this underground world is the New Cave of Villanova; a place where to feed our eyes with images of uncontaminated nature, where we can abandon our routine and let ourselves be surprised by the wonders that man cannot imitate or build. The magnificence of this cave is enriched by a rare peculiarity; the Grotta Nuova is in fact a "cave in the Flysch", formed in contact between two completely different types of rock. The water has exercised two different karst actions on these rocks, shaping tunnels and rooms that vary in size and morphology every few tens of meters, offering the amazed gaze of those who visit them changing environments, of incomparable charm, similar to immense sculptures of stone in which white calcite gems are set. With almost 9 km of development, it is the largest of its kind known so far in Europe and in most of the world, and it is the only one to be equipped for underground tourism
3- Cave of San Giovanni D’Antro
Going back by car to the Natisone Valley, leaving the village of San Pietro behind and continuing in the direction of Pulfero, a picturesque village of ancient houses appears from the harmony of the woods. the town of Antro. The surrounding area took its name from the village, indicated since ancient times as Gastaldia d'Antro. Not far from the town, nestled in a rocky wall, there is the "cave of San Giovanni d'Antro". The entrance to the cave is located about 350 meters above sea level and the geological path, currently explored for 4500 m, develops horizontally over several floors. The exploratory tourist route open to visitors and easily accessible for everyone for 300 meters is characterized by a comfortable semi-artificial path that allows the hiker to enter the bowels of the earth. The first impact in this cavity is spectacular: on a vertical rock wall (from which, in rainy periods, an underground river rushes out) stands a steep (but easy) staircase leading to the first room of the cave, where the visitor is in front of the extraordinary fifteenth-century church carved in the rock by Andrea da Skofia Loka and adorned by the splendid wooden altar by Bartolomeo Ortari.
4- Torri di Slivia cave
On May 1, 2012, after forty years of closure, the cave of the Torri di Slivia reopened, still considered one of the wonders of the Trieste Karst. It has been known since the late nineteenth century and the number 22 identifying the regional cadastre indicates that this was among the first to be explored on the Karst of the over 3,000 caves currently piled up. Today there are two entrances: a natural well about 30 meters deep, from which it is possible to descend only with speleological equipment, and an artificial entrance that, through a staircase of 200 steps, leads the public to the heart of the cave, about 60 meters underground The cavity develops in rooms adorned with beautiful sails, eccentric, stalactites and stalagmites, up to 7 meters high and even 10 tons heavy. The most famous are the stalagmite towers, a group of eight concretions of different sizes, from which the cave takes its name. Inside, besides the small insects typical of the underground environment, there is a mixed colony of bats: three species that live, hibernate and reproduce in caves. These are protected by partial illumination of the cavity and by specific prescriptions that regulate the flow of visitors based on the rhythms of nature. The cavity is located under one of the properties of the Le Torri di Slivia farm and is an example of active protection of a naturalistic site born from a close collaboration with the Natural History Museum of Trieste and with the Faculty of Geology of the University of Trieste
5- Giant cave
Considered the largest tourist cave in the world, it has been included in the Guinness Book of Records since 1995. Open to the public since 1908, it consists of an immense cavity - 280 m long. 65 m wide and with a 107 m dome vault - in which, at various altitudes, large galleries converge, remains of an ancient river network abandoned by the water a few million years ago. It is located in the town of Borgo Grotta Gigante in the municipality of Sgonico, 1 km from Opicina and a few kilometers from Trieste. A path of zigzag ramps leads to the base of the cave; the show is unique both for the majesty of the cavity and for the richness and variability of the shapes and colors of stalactites and stalagmites, highlighted by skilful lighting. The route takes place around the base of the Great Hall, passing near the Pulpit and the Palma which are imposing stalactites, the latter almost 7 m high; the path then continues until it reaches the Ruggero column, a stalagmite almost 12 m high. Leaving the column behind you arrive at the Altar room, a lateral cave characterized by large stalactites and a "calcitic" basin with water. Approaching the exit you can see the skeleton of an Ursus speleus dating back to the presidential age. The exit takes place along a path that climbs alongside the back wall, through an artificial tunnel, which leads to the Belvedere, the highest point of the cave, from which you can enjoy a breathtaking view of the Great Cave. The internal temperature of the cave remains constant all year round (11/12 ° C). The cave houses scientific equipment: a seismographic center and a large pendulum capable of making the effects of sea tides and groundwater floods measurable on the structure. The friendly cave, A story for everyone: The Giant cave seen through laser scanner technology with the new virtual path (also accessible to people with walking difficulties)