Passage 5.20.9
ταῦτα μὲν δὴ αὐτὸς ἑώρων ὀρυσσόμενα· ναὸν δὲ μεγέθει οὐ μέγαν καὶ ἐργασίᾳ Δώριον Μητρῷον καὶ ἐς ἐμὲ καλοῦσιν ἔτι, τὸ ὄνομα αὐτῷ διασώζοντες τὸ ἀρχαῖον· κεῖται δὲ οὐκ ἄγαλμα ἐν αὐτῷ θεῶν Μητρός, βασιλέων δὲ ἑστήκασιν ἀνδριάντες Ῥωμαίων. ἔστι δὲ ἐντὸς τῆς Ἄλτεως τό τε Μητρῷον καὶ οἴκημα περιφερὲς ὀνομαζόμενον Φιλιππεῖον· ἐπὶ κορυφῇ δέ ἐστι τοῦ Φιλιππείου μήκων χαλκῆ σύνδεσμος ταῖς δοκοῖς.
These things indeed I myself saw while they were being excavated. There is also a temple, not large in size and Dorian in workmanship, called the Metroön even up to my own day, preserving its ancient name. It contains no statue of the Mother of the Gods, but statues of Roman emperors stand therein. Within the Altis are located both the Metroön and a circular structure called the Philippeion; and atop the Philippeion is a bronze poppy that joins together the beams.