In arid and semi-arid areas such as southern Africa, rock hyrax (Procavia capensis) middens represent an exceptionally valuable source of late Quaternary palaeoenvironmental information. Pollen and stable isotope data derived from two rock hyrax middens extracted from a site, De Rif, in the Cederberg Mountains of the southwestern Cape, casts new light on climatic changes that occurred during the last glacial-interglacial transition (LGIT) and the Holocene, and how the region’s vegetation appears to have been remarkably resilient to these changes. Since the midden in question accumulated during a period encompassing both the late glacial and the Holocene, significant changes in vegetation community composition as recorded in the pollen record would be expected in response to environmental changes characteristic of the contrast between glacial and interglacial climates. However, the pollen assemblages in general indicate that mountain fynbos remained dominant throughout the record and that most of the pollen taxa exhibited only muted frequency variations over the period in question. This finding is inconsistent with indications of marked climatic variations recorded in the stable isotope records for the same midden. An analysis of the geological setting and the bioclimatic affinities of the taxa suggest that the explanation for this inconsistency may lie in the dominating influence of sandstone substrates and the relative resilience of mountain fynbos vegetation composition to climate change.