Germanicopolis (Greek: Γερμανικόπολις) also Caesarea Germanica, was an ancient town in Isauria, Bithynia, on the Gelbes river, not far from Prusa (modern Bursa in Turkey). In earlier times it was called Helge, Helgas or Booscoete (Βοὸς κοίτη), Plin. v. 40. Modern scholars locate the town at the village of Tahtalı (Coordinates: ).
- This article incorporates text from a publication now in the public domain: Smith, William, ed. (1854–57). "article name needed". Dictionary of Greek and Roman Geography. London: John Murray.
- Richard Talbert, Barrington Atlas of the Greek and Roman World, (ISBN 0-691-03169-X), Map 52 & text.
- William Hazlitt, The Classical Gazetteer: A Dictionary of Ancient Geography, Sacred and Profane, p. 161