Passage 2.17.1
Μυκηνῶν δὲ ἐν ἀριστερᾷ πέντε ἀπέχει καὶ δέκα στάδια τὸ Ἡραῖον. ῥεῖ δὲ κατὰ τὴν ὁδὸν ὕδωρ Ἐλευθέριον καλούμενον· χρῶνται δὲ αὐτῷ πρὸς καθάρσια αἱ περὶ τὸ ἱερὸν καὶ τῶν θυσιῶν ἐς τὰς ἀπορρήτους. αὐτὸ δὲ τὸ ἱερόν ἐστιν ἐν χθαμαλωτέρῳ τῆς Εὐβοίας· τὸ γὰρ δὴ ὄρος τοῦτο ὀνομάζουσιν Εὔβοιαν, λέγοντες Ἀστερίωνι γενέσθαι τῷ ποταμῷ θυγατέρας Εὔβοιαν καὶ Πρόσυμναν καὶ Ἀκραίαν, εἶναι δὲ σφᾶς τροφοὺς τῆς Ἥρας·
The Heraion is situated fifteen stades to the left of Mycenae. Along the road flows a stream known as Eleutherion, whose water is used by the women involved in the sanctuary for purification and for the secret rites of the sacrifices. The sanctuary itself lies lower than Euboea; for this mountain they call Euboea, saying that the river Asterion had daughters named Euboea, Prosymna, and Acraea, who became nurses of Hera.