Abstract Seven borehole cores were analysed to reconstruct the Pleistocene evolution of the Pego-Oliva Basin (Mediterranean coast, Iberian Peninsula). A total of 295 samples were recovered for amino acid racemization (AAR) dating, and 77 samples for sedimentological, palaeontological and biomarker determination, with two objectives: (1) to establish a chronological framework (especially for Middle Pleistocene); and (2) to obtain data on the palaeoenvironment. AAR proved that the record covers approximately 650 ka in which no important hiatuses occurred, although minor ones cannot be discarded. AAR provided valuable information on differential subsidence rates, and Marine Isotope Stages (MISs) 15–1 were identified. Litho- and biofacies allowed the identification of distinct palaeoenvironments through time, with the constant presence of a marsh/lagoonal environment with brackish or saline water with continental or marine influence. Remains of marine molluscs allowed the determination of periods of highstand sea level. Biomarkers indicated a constant input from terrestrial plants, and allowed definitions of periods with variable water mass and environmental moisture. As in other Mediterranean littoral areas, facies with a marine influence occurred mainly during odd MISs, indicating periods of highstand sea level. In contrast, alluvial-fan progradation and continental brackish wetlands developed during even MISs.