§24.4.1πρὸς μὲν οὖν τῷ Πόντῳ τὸ Αἷμόν ἐστιν ὄρος, μέγιστον τῶν ταύτῃ καὶ ὑψηλότατον, μέσην πως διαιροῦν τὴν Θρᾴκην·
Now, near the Pontus there is Mount Haemus, the largest and highest of those in that region, dividing Thrace roughly in the middle.
ἀφʼ οὗ φησι Πολύβιος ἀμφοτέρας καθορᾶσθαι τὰς θαλάττας, οὐκ ἀληθῆ λέγων· καὶ γὰρ τὸ διάστημα μέγα τὸ πρὸς τὸν Ἀδρίαν καὶ τὰ ἐπισκοτοῦντα πολλά.
From this mountain Polybius says that both seas can be seen, which is not true; for not only is the distance to the Adriatic great, but also the obstacles obscuring the view are many.