This is perhaps the most famous cave in Italy for its location, accessibility, and the volume of tourists visiting every year. It is located on the coast of the island of Capri, and must be entered by boat. What is most amazing about this cave is the color of the water against the light, making it a magical environment that only Mother Nature is capable of delivering.
These caves are called karst caves, and we find them in the Liguria region. This is a perfect side trip if you are already in the area visiting Cinque Terre, a very popular tourist spot. The entire path is half a mile long and features several ponds and one river. The inside of the caves presents many colorful rocks that date back three quarters of a million years.
In the area of Salerno, not far from Naples, it is possible to visit this group of caves. They are famous for their various kinds of stalagmites and stalactites. The caves go on for miles.
Further south in our journey among the Italian caves we reach Castellana, near Bari. The caves have an immense entrance and house a vast series of holes and tunnels that descend into the depths, and make it almost impossible to find your way. Therefore tourists are strictly only allowed on organized tours and on defined itineraries. The cave visit can be enhanced by a visit to the impressive speleologist (the scientific study of caves) museum nearby.
Grotta del Cavallone
A little bit further north, in Abruzzi to be precise, we find another wonderful cave. During World War II Grotta del Cavallone hosted the entire population of the village nearby and it saved many lives. Inside, the cave features several chambers that have inspiring names such as the "Enchanted Forest," "The Elephants' Room," and "The Pantheon." All of these are quite beautiful.
Located near Duino, in the province of Trieste, this cave has important historical and religious value, as it was a site dedicated to pagan rituals. In fact it is still possible to see a basic altar made of natural limestone; this is a testimony to its early sacred character.
Ear of Dionysius
This is actually a non-natural cave but due to its tourist relevance we would like to list it as a "must-see." It is located in the park where the Syracuse amphitheatre is, in southern Sicily. The shape of the cave is an "S" and it resembles an ear. It is possible to speak and be heard anywhere in the cave from the entrance; the sound is amplified up to 16 times its original level. The proximity of the theatre makes the Ear of Dionysius a popular spot for curious people willing to try out the ancient acoustic trick.
This group of caves is one of the most famous in the country. Located in the central region of Marche, the caves were reportedly first discovered in 1948, though most sources state that 1971 is when they began to be explored. They feature a series of linked chambers, one of which is a bizarre shape that feels like an endless tunnel when in fact it is one very long chamber. Today the caves are open to the public for daily visits, and they are estimated to be around 190 million years old.
Up in the northeast, close to Trieste, we find the Giant Cave, the largest cave open to the public in the world. Although several tunnels are linked to the cave, there is actually only one immense chamber. The cave contians some important instruments to measure the movements of the Earth's crust and the sea tides. The overall tour doesn't take more than one hour.
Grotta dei cordari
This cave is interesting because is a combination of a natural cave and the work of mankind. It is closed to the public, but truly fascinating to see even from the outside.
Now, let's go to Sardinia across the sea. This cave has a stalagmite nearly 40 meters tall, almost in the middle of the chamber. The cave also features a long dark hole which is reported to have been used in ancient, pre-Roman times, to sacrifice human lives. This makes it quite a sinister spot to visit.
Remaining on Sardinia we find the Cave of Neptune, the Roman god of the sea. The cave was discovered in the 18th century by a local fisherman, and it has become a hot tourist destination. This grotto is similar to the Blue Grotto in Capri, however this has both a sea entrance and another from the land. Beneath the cave lies a salty lake. Nearby are two other caves, including a green cave that contains prehistoric graffiti.
This cave is actually underwater and it is the largest in the Mediterranean Sea. Not far from Neptune's Grotto, off the coast of Sardinia, the cave is big and features several entrances. Additionally, this cave is a virtual aquarium for divers, housing its famous red coral, plants, and fish typical of the Mediterranean.