Passage 3.23.7
λέγουσι δὲ καὶ ὡς οἴκοθεν ἐκ τῆς Ἐπιδαύρου δράκοντα ἐπαγομένοις αὐτοῖς ἐξέφυγεν ἐκ τῆς νεὼς ὁ δράκων, ἐκφυγὼν δὲ οὐ πόρρω κατέδυ θαλάσσης, καί σφισιν ὁμοῦ τῶν ὀνειράτων τῇ ὄψει καὶ ἀπὸ τοῦ σημείου τοῦ κατὰ τὸν δράκοντα ἔδοξεν αὐτόθι καταμείναντας οἰκῆσαι. καὶ ἔνθα ὁ δράκων κατέδυ, βωμοί τέ εἰσιν Ἀσκληπιοῦ καὶ ἐλαῖαι περὶ αὐτοὺς πεφύκασιν.
They say also that as they were bringing a serpent from Epidaurus, the serpent escaped from the ship, and after escaping plunged into the sea not far away. Prompted both by the dreams they saw and by the sign given by the serpent, they decided to settle and dwell in that very place. And where the serpent sank into the sea stand altars to Asclepius, with olive trees growing around them.