In the municipality of Festion, northeast of Kainuri, at an altitude of 688 meters is the castle of Vlochos. There, on the top of the hill of the same name, on the western slope of Panaitolikos, in ancient times there was the ancient city of Thestia.
The city was named after the mythical king Thestius. To the south and west of the local Acropolis were walls, on which several sections without towers have been preserved. The surviving pylon is similar to the Mycenaean Tiryns column.