A medieval defense fortification, which served as the citadel of Kardamyla.
It is accessible via an old hiking trail, which has been signed and renovated. Tradition has it that it owes its name to an old lady ("gria" in Greek) who climbed up from Kardamyla over the steep rocks, in order to save herself from pirates. Still extant in the fortress are two towers connected by a wall.
The eastern tower is semi-circular backed by the wall, and the western tower is round. This whole complex stands on the south side of the flat top of the mountain. There is a sheer drop-off on all the other sides, which obviated the need to construct a defense wall. Tradition has it that the western tower communicated with the well of Koulalas through a tunnel, which provided the people shut up in the fortress with water.
The walk up to the castle is worth it, as the view is magical.