The frozen caves are only formed in winter, when the water that comes down from the glaciers in summer, due to the melting of the snow, solidifies for good. Every year there are different caves that can be more or less spectacular, more or less accessible and above all more or less safe. A cave can disappear at any moment and it is for this reason that at the beginning of each winter there are some real surveys to check if the caves of the previous year still exist, if they can be visited and therefore safe or if they are disappeared, replaced by others that are tested in the same way to understand their safety.\r