The Mougkri cave in Rethymno prefecture is the longest cave of Mount Kouloukonas, on Koufoto hill near the village Sises, 44 kilometers from the city of Rethymno.
Historically known to residents of the region, the Mougkri cave, with an area of about 2 acres, was explored and mapped in 1992. The findings indicate that it has been used by people at least since the Minoan era and it was a place of worship in antiquity. A Roman inscription was also found inside the cave. The legends that have survived until today want the cave being inhabited by devils.
The Mougkri cave, at an altitude of 253 meters, forms within the lower layers of the limestone plates, along one of the many rifts that affected the region. The cave is quite impressive with rich wall decoration including flowstones, curtains, stalactites, stalagmites, corals and few helictites. The cave consists of 5 large halls with steep slopes that at some points become vertical. Shortly after the entrance, going through a passage to the right with low roof, a small hall appears where bats are nesting, while in front of the entrance hall and in the distance, the great hall of the cave can be seen. In the last and largest chamber there are large stone basins, up to 3 meters, indicating that in other times this part was submerged.
The access to the Mougkri cave is allowed only to specialists.