Passage 2.15.2
ἐκ Κλεωνῶν δέ εἰσιν ἐς Ἄργος ὁδοὶ δύο, ἡ μὲν ἀνδράσιν εὐζώνοις καὶ ἔστιν ἐπίτομος, ἡ δὲ ἐπὶ τοῦ καλουμένου Τρητοῦ, στενὴ μὲν καὶ αὐτὴ περιεχόντων ὀρῶν, ὀχήμασι δέ ἐστιν ὅμως ἐπιτηδειοτέρα. ἐν τούτοις τοῖς ὄρεσι τὸ σπήλαιον ἔτι δείκνυται τοῦ λέοντος, καὶ ἡ Νεμέα τὸ χωρίον ἀπέχει σταδίους πέντε που καὶ δέκα. ἐν δὲ αὐτῇ Νεμείου τε Διὸς ναός ἐστι θέας ἄξιος, πλὴν ὅσον κατερρυήκει τε ὁ ὄροφος καὶ ἄγαλμα οὐδὲν ἔτι ἐλείπετο· κυπαρίσσων τε ἄλσος ἐστὶ περὶ τὸν ναόν, καὶ τὸν Ὀφέλτην ἐνταῦθα ὑπὸ τῆς τροφοῦ τεθέντα ἐς τὴν πόαν διαφθαρῆναι λέγουσιν ὑπὸ τοῦ δράκοντος.
From Cleonae to Argos there are two roads: one is shorter and suitable for lightly equipped men, while the other passes through the place called Tretus; although narrow itself, being hemmed in by mountains, it is nonetheless more convenient for vehicles. Among these mountains there is still shown the cave of the lion, and the place called Nemea is situated about fifteen stades distant. At Nemea itself is a temple of Nemean Zeus, worthy of being seen, although its roof has collapsed and no statue remains. Around the temple is a grove of cypresses, and here, they say, Opheltes, laid down by his nurse on the grass, was killed by the serpent.