Just south of Areopoli near the village of Pyrgos Dirou are the Diros Caves where you board a small boat and get paddled and punted through some spectacular chambers with fascinating rock formations which are lit to make them look even more wonderous. There is some walking but the boat is the best bit, especially for kids [and me].
The ticket office is on the main road before it bends towards the cave entrance which is rather weird. There is an evocative monument to the local women who drove out invading Ottomans in 1826 near the cave entrance.
It is a bit touristy and the length and route of the boat trip inside the cave may depend on the height of the water. Your boatman may be friendly, chatty and informative or may be a misery, speak no English and shoot through the caves making it difficult to take a good photo.
On my last visit the water was high and I smacked my head on a stalagtite. Life jackets are provided but not helmets unfortunately.
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