Herius
Ἥριος
Herius (Ἥριος). Ptolemy (2.8.1) places the Herius on the coast of Gallia Lugdunensis, between the Brivates Portus and the Vindana or Vidana Portus. Ptolemy's latitude of the mouth of the Herius (49 1/4°) makes it nearly as far north as the outlet of the Seine. D'Anville [DURETIE] supposes the Herius to be the Vilaine, the first large river north of the Loire. He adds (Notice, &c., Herius Fluv.) that the passage of the Vilaine between Roche-Bernard and the mouth of the river is now called Treig-hier, and that we may readily believe Treig-hier to be a corruption of Trajectum Herii. This may be so; or Treig-hier may be the old Celtic name. Some geographers assume the Herius to be the small river Auray north of the Vilaine; but this is only a guess like the other. [G.L]>
From William Smith (ed.), Dictionary of Greek and Roman Geography. Text provided under a CC BY-SA license by Perseus Digital Library, http://www.perseus.tufts.edu, with funding from the National Endowment for the Humanities and Tufts University. Data accessed from https://github.com/PerseusDL/canonical-pdlrefwk/ on 17 October 2026.