The Eifelgau derives its name from the Eifel mountains between the Rhine, Ahr, Rur, Our, Sauer and Moselle rivers.
[1] It encompasses the source regions of the rivers Erft, Urft, Kyll and Ahr, and is thus located mainly in the northern and northwestern foothills of the Eifel.
[3] Roughly around the 7th century the Franks used the term Ardennes for the mountain range and divided their empire into gaus.
In the meantime the German part of the mountain range became known as the "Eifel", while the Belgian, French and Luxembourgian areas on the other side of the border became the "Ardennes".
The gau was ruled by gaugraves ("gau counts"): Ahrdorf, Antweiler, Aremberg, Arloff, Baasem, Bad Münstereifel, Barweiler, Betteldorf, Bewingen, Bouderath, Buir, Dahlem, Engelgau, Frohngau, Gilsdorf, Hillesheim, Holzmülheim, Insul, Iversheim, Kerpen, Kesseling, Lammersdorf, Lessenich, Leudersdorf, Lindweiler, Lommersdorf, Marmagen, Müsch, Nettersheim, Nohn, Oberbettingen, Pesch, Prüm, Reifferscheid, Ripsdorf, Roderath, Satzvey, Schmidtheim, Schuld, Sellerich, Steffeln, Tondorf, Üxheim, Weyer, Wiesbaum and Zingsheim.