Solfatara
In the territory of the city of Pozzuoli, about 10 kilometers from Naples, you can find the crater of Solfatara formed about 4000 years ago. Solfatara has a diameter of 770 meters and characteristic are the gas fumes smelling of rotten eggs that escape through the Solfatars named after the crater. There is also an ancient Roman sauna here, where the volcanic gases were used medicinally. At the moment, unfortunately, the crater can not be visited due to a closure.Cratere Degli Astroni
As a nature reserve, the green oasis of Astroni Crater is perfect for a quiet getaway. Many local plant and animal species thrive here, but the volcanic activity is not nearly as visible as at Solfatara.