Passage 3.21.9
ὃν δὲ ὀνομάζουσι Γυθεᾶται Γέροντα, οἰκεῖν ἐν θαλάσσῃ φάμενοι, Νηρέα ὄντα εὕρισκον· καί σφισι τοῦ ὀνόματος τούτου παρέσχεν ἀρχὴν Ὅμηρος ἐν Ἰλιάδι ἐν Θέτιδος λόγοις· ὑμεῖς μὲν νῦν δῦτε θαλάσσης εὐρέα κόλπον, ὀψόμεναί τε γέρονθʼ ἅλιον καὶ δώματα πατρός. Hom. Il. 18.140-141 καλοῦνται δὲ ἐνταῦθα καὶ πύλαι Καστορίδες, καὶ ἐν τῇ ἀκροπόλει ναὸς καὶ ἄγαλμα Ἀθηνᾶς πεποίηται.
The one whom the inhabitants of Gythium call the "Old Man," whom they claim dwells in the sea, I found to be Nereus. Homer gave them the source of this name in the Iliad, in the words of Thetis: "But you now descend into the broad bosom of the sea, to behold the aged man of the sea and the dwellings of our father." Here also are gates named Castorides, and on the acropolis there is built a temple and statue of Athena.