It is a located exactly underneath the Castle, at the medieval city of Skiathos, which you can reach by car up to a point, and then you have to walk. It is a wonderful experience that will combine a visit to one of the most significant sights of the island, and a cool dip into the crystal clear waters of the beach. You can also access it by boat. Give our regards to Apostolis, who has the tavern there, and he has watching over the area for years.