Passage 6.20.1
τὸ δὲ ὄρος τὸ Κρόνιον κατὰ τὰ ἤδη λελεγμένα μοι παρὰ τὴν κρηπῖδα καὶ τοὺς ἐπʼ αὐτῇ παρήκει θησαυρούς. ἐπὶ δὲ τοῦ ὄρους τῇ κορυφῇ θύουσιν οἱ Βασίλαι καλούμενοι τῷ Κρόνῳ κατὰ ἰσημερίαν τὴν ἐν τῷ ἦρι, Ἐλαφίῳ μηνὶ παρὰ Ἠλείοις.
Mount Kronion extends, as I have already described, alongside the terrace and the treasuries situated upon it. At the summit of this mountain, those called the Basilae sacrifice to Kronos at the spring equinox, during the month of Elaphios according to the Eleians.