Note 2809 — BOOK IV. AN ACCOUNT OF COUNTRIES, NATIONS, SEAS, TOWNS, HAVENS, MOUNTAINS, RIVERS, DISTANCES, AND PEOPLES WHO NOW EXIST OR FORMERLY EXISTED.
John Bostock translation
According to Hardouin, Pliny here speaks of the other side of the mountainous district called Higher Hungary, facing the Danube and extending from the river Theiss to the Morava.