The geomorphology of western Galicia is reconsidered in the light of Nonn's monograph (1966), and an envelope map of the relief, as defined by Stearns (1967) and Pannekoek (1967), and an interpretation of the latter are also presented. The envelope map shows more clearly than an ordinary contour map that the major relief features are not controlled by the lineations of the Hercynian basement but by late- or post-Hercynian faults, some of which may have been reactivated in Tertiary times. Concerning the geomorphological evolution, the author agrees with most of Nonn's conclusions, although there is some divergence on minor points. The isolated mountain massifs, capped by remnants of older pediplains, already existed in Upper Miocene times. The depressions between these massifs, including the long median depression, are, much more than was previously presumed, the result of erosion along pre-existing fault lines, first during the Miocene and then during the Pliocene: only a few are bordered by post-Pontian fault scarps. Finally, tentative reconstructions of the Upper Miocene and the Pliocene topography are given.