AbstractThe Pleistocene rock‐stratigraphic record is accorded more or less traditional time‐stratigraphic interpretation which was held widely before application of an Irish developmental model in 1960. The following sequence of events are recognised: (1) Complete glaciation, of indeterminate age, which antedated the raised beach interglacial. (2) The raised beach episode which is shown to be the last (Ipswichian) interglacial. (3) The last (Devensian/Weichselian) glaciation, followed by possible readvance in northwest and northeast Wales; prior and subsequent to glaciation periglacial conditions obtained. It is shown that the Irish model, relying heavily as it does on the equation of rock and time stratigraphy, is inapplicable in Wa