Even more impressive from the surface carst is the underground carst. There is a small amount of running water on the surface, as most of it is absorbed in the subsoil and moves underground through the multiple channels of the water-soluble limestone. In the mountainous area of Itanos only, more than 82 caves, chasms, sinks and underground rivers have been recorded and the total explored routes are more than 6,000 meters and basically provide a bilge system for the province.
From here, the waters flow to the east to finally end up in various springs near the east coastline, like the ones in Zakros and Hohlakia. The past few years, the municipality of Itanos in cooperation with the speleological Club of Crete are working towards the creation of a speleological park. Many of the caves of Sitia, and of Crete in general, are connected with religious rituals and traditions dating back to the Minoan period. For the time being, the caves are not open to the public.
However, it is possible to access some of them with the appropriate equipement. The most important caves of the region that functioned as sites of worship in the past are: