According to pollen analysis, Marine Isotope Stage 3 (MIS3, ca. 60-30ka) is characterized in southern Europe by dynamic alternations of forest vs. semi-arid area expansion in accordance with the warming and cooling, respectively, of the sea-surface temperatures. It is in this context of rapid fluctuations that the Neanderthal occupation of the northeastern Iberian Peninsula took place. This paper sets forth a synthesis of the previously published environmental and climatic data obtained from the small vertebrates (herpetofauna and small mammals) of the Neanderthal localities of Cova del Gegant, Abric Romani, l'Arbreda cave, Canyars and Teixoneres. Using habitat weighting and mutual climatic range methods to reconstruct the environment, temp...