Pollen and mollusc deposits in a sedimentation series laid down in the Dättnau Valley during the Late Glacial and extending into the Post-glacial were studied. At the same time a large number of fossil wood finds embedded in the series were dated and analysed dendrochronologically. It was possible to reconstruct vegetational and climatic developments from the onset of the Bölling (13'000 to 12'500 y BP) until well into the Boreal (ca. 9'000 y BP). The findings from the various analyses show good agreement with each other. The Late Glacial is seen to have comprised two intervals: the continuous, rather moist, warm Bölling/Alleröd period, and the subsequent dry, cold Younger Dryas. The profile ceases in the early Boreal, after the transition from the Late Glacial to the Post-glacial. The beginning of the Bölling is very clearly indicated by the pollen diagram, the fossil wood, and the mollusc remains, as is the transition from the Alleröd to the Younger Dryas. The subsequent transition to the Post-glacial is clearly reflected in the pollen diagram, although the wood finds cease at the end of the Alleröd, and the mollusc remains become uninterpretable shortly before the climatic change to the Post-glacial. The first δ¹⁸O measurements, ever published for land snails, show a clear distinction between the Alleröd and the Younger Dryas.