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Abstract. This paper presents the results of pollen analyses from organic sediments of seven cores (299 spectra) in a mountainous area of the north-west Iberian peninsula. The pollen diagrams, supported by seven x4c dates, are used to construct a regional pollen sequence covering the main stages of vegetation dynamics, from the last phases of the Late-glacial until the present. During the Late-glacial Interstadial an important development of cryophilous forests (Betula and Pinus) was recorded, although various mesophilous and thermophilous tree elements were also present. The Younger Dryas, palynologically clearly defined, is characterized by an important reduction in tree pollen percentages and the expansion of steppe formations (Poaceae and Artemisia).At the beginning of the Holocene, there was an expansion of Quercus and a spread of other trees, which combined to give a vegetation cover of varied composition but dominated by mixed deciduous forests. Such forest formations prevailed in these mountains until 3000 years ago, when successive deforestation phases are recorded at various times as a result of increased farming activity. The results are compared with data from other mountainous areas in the northern Iberian peninsula and southern France.

We used pollen analysis to evaluate the territories and the northermost slopes of the Cantabrian-Atlantic Mountains). During these dynamics of sclerophyllous arboreal taxa during the last 16,000 years. Quercus ilex type pollen and, to a periods, there is no indication of the presence of Quercus ilex pollen in the northwestern territories, which would lesser degree, other sclerophyllous elements (e.g. Olea and Phillyrea) have been documented during the Late-explain the absence of this species in the present-day landscape. Despite the widespread distribution that glacial in the majority of the sequences obtained in continental territories in the north of the Iberian sclerophyllous elements have maintained during the last 16,000 years, they have never attained a peninsula, as well as in the eastern coastal/sub-coastal area in the Cantabric region. During the Late-glacial predominant role in the landscape, having a smaller representation, both during hotter and colder phases, and the Holocene, sclerophyllous elements became widespread in many areas of the north Iberian than deciduous forests, pine forests and mixed forests. peninsula (the Sil, Duero and Ebro depressions and the southernmost slopes of adjacent mountains), with Key words. Iberian peninsula, sclerophyllous forests, Quercus ilex, species range, Late-glacial, the smallest pollinic representation of these taxa being for the most septentrional areas (coastal/sub-coastal Holocene, vegetation history, palynology.

Three NW Iberia Cantabrian Mountain pollen records are presented. They reflect the main Holocene climatic shifts in the North Atlantic region as recorded in the isotopic data from Greenland ice, Irish speleothems and reconstructed sea surface temperatures. Two brief forest regression episodes reconstructed from pollen may be synchronous with GH‐11.2 and GH‐8.2 events. At mid‐altitude, two woodland expansion phases (7000–6000 14C yr BP and 4000–2500 14C yr BP) are separated by a phase of heaths and peat deposits. Major woodland declines occurred during the Galician‐Roman Period (which includes the Bronze Age, the Iron Age and the Roman occupation) and from the end of the Medieval Period. The pollen data, backed up by archaeological and historical sources, suggest climatic impact of the Iron Age Cold Period, but are indecisive concerning the Little Ice Age. However, the pollen records do not support any significant ‘Neoglacial’ period (4000–3000 14C yr BP) influence on NW Iberia.

The pollen record at Area Longa is the westernmost sequence available for investigation of the last glaciation in continental Europe. It is located in a region, NW Iberia, for which data from times earlier than the late glacial period are scarce. It comprises a series of exposed limnetic levels that lie above an Eemian (Oxygen Isotope Stage [OIS] 5e) beach and are separated by inorganic layers. The oldest limnetic level (Level I), attributed to the early glacial period (OIS 5a to OIS 5d), shows a dominance of woodland with high proportions of Fagus pollen and is tentatively identified with St. Germain I. The lower pleniglacial (OIS 4) Level II records a stadial landscape of grassland and shrub. Level III, from the pleniglacial interstade (OIS 3), reflects a complex period in which three warmer woodland phases alternated with periods of more open vegetation. This cyclical behavior correlates with the ice core isotope record and with the general tendencies observed in other Würmian pollen records, but the composition of our pollen profiles differs from those observed in these other records. In NW Iberia, the dominant trees were deciduous taxa, not conifers. Of particular note is the presence of lowland Fagus woodlands during the pre-Würm, and the occurrence of Carpinus considerably farther west than the boundary of its current distribution in the Iberian Peninsula.