If you follow the hiking trail D from Megalopotami into the mountains, you will eventually come to the beautiful chapel of Agios Joannis, in which an Ionic column capital was built into the front wall. There are other ancient remains in front of it. There must have been an ancient sanctuary in the area, because nobody "just" lugs marble columns up the mountain here. If you follow the path further up, you come to a plateau, on the northeastern edge of which there are ancient remains of an oil press and a column of volcanic rock. The ceramic remains scattered around go back to classical Greek times (black glazed fragments).