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This study uses luminescence and 14C accelerator mass spectrometry procedures to date relevant glaciofluvial and glacial deposits from the south-central and southeastern Pyrenees (Andorra-France-Spain). We distinguish two types of end-moraine complexes: (1) those in which at least a far-flung moraine exists beyond a frequently nested end-moraine complex (the most common) and (2) those in which a close-nested end moraine encompasses at least two glacial cycles. Both types formed within six distinctive glacial intervals: (1) A penultimate glacial cycle during Marine Oxygen Isotope Stage (MIS) 6 and older glaciofluvial terraces occurred beyond the range of the luminescence dating method. (2) An early glacial advance in MIS 5d (~97 -15/+19 ka) was followed by glacial retreat during MIS 5c (< 91 ± 9 ka). (3) The last maximum ice extent (LMIE) was in early MIS 4 (~74 ± 4.5 ka). (4) Unexpectedly, glaciers thinned during the second half of MIS 3 (~39 -6/+11 ka). (5) During the MIS 3-2 transition, glaciers subsequently fluctuated behind the LMIE limits. (6) The global last glacial maximum (LGM) started as early as ~26.6 ± 0.365 ka b2k, and the corresponding end moraines were built behind the LMIE limits or merged with it, forming close-nested moraines.

The Navamuno peatbog (Sierra de Bejar, western Spain) is a ~14 ha pseudo-endorheic depression with boundaries defined by a lateral moraine of the Cuerpo de Hombre paleoglacier and fault-line scarps on granite bedrock. The stratigraphy of the Navamu~no peatbog system is characterized here using borehole data to a depth of 20 m. An integrated interpretation from direct-push coring, dynamic probing boreholes and handheld auger drillings advances our knowledge of the Navamu~no polygenetic infill. Correlating this data with those obtained in other studies of the chronology and evolutionary sequence of the Cuerpo de Hombre paleoglacier has enabled us to establish the sequence of the hydrological system in the Navamuno depression. During the Late Pleistocene (MIS2), the depression was dammed by the Cuerpo de Hombre glacier and fed by its lateral meltwaters, and was filled with glaciolacustrine deposits. The onset of the Holocene in Navamuno is linked to a flat, fluviotorrential plain with episodes of local shallow pond/peat bog sedimentation. This evolutionary sequence is congruent with the age model obtained from available radiocarbon dating, obtaining 19 ages from ~800 cal yr BP (at depth 1.11 m) to ~16800 cal yr BP (at depth 15.90e16.0 m). Finally, the sedimentary record enabled interpretation of the environmental changes occurring in this zone during the late glacial (from the Older Dryas to the Younger Dryas) and postglacial (Holocene) stages, placing them within the paleoclimatic context of the Iberian Peninsula and Mediterranean regions.