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Theopetra Cave preserves a 6.4-m-thick sedimentary sequence characterized by alternating, mostly water-lain sediments, and multisequence burnt layers. Eighteen principal radiocarbon ages provide temporal control for this sequence. The sediments of the cave were examined using micromorphological techniques, which involves the study of petrographic thin sections produced from resin-impregnated, undisturbed blocks of sediment. Several distinct cold periods are recorded in the sediments. The earliest of these represents a major cooling, and it is tentatively assigned to Oxygen Isotope Stage 4 on the basis of the sedimentation rate and the associated sequence of events. A brief cold event affected the uppermost part of a burnt layer dated to ca. 46 kyr B.P., but its effect ended well before 40 kyr B.P. The second major cold phase spans the period between around 33 kyr B.P. and the end of Last Glacial Maximum (16 kyr B,P.). However, there is ample evidence for a milder interval around 25 kyr B.P. It is argued that a distinctive, albeit weaker and brief cold peak, at about 11 kyr B.P., provides the strongest evidence so fax obtained in Greece for the Younger Dryas event. Both major cold phases are characterized by a sequence of events that started with alternating freeze-thaw activity and phosphate cementation and ended with erosion. The return to milder conditions is accompanied by natural aggradation inside the cave. The aggradation accelerated throughout much of the glacial phase and ended soon after the Last Glacial Maximum. In addition, two other major erosional events are recorded in the cave. The first may be correlated with an early Holocene arid interval at around 7.5 kyr B.P. The second is tentatively assigned to the end of Neolithic, although it is not clear if it was triggered by a climatic change or by human disturbance of the landscape. The general sedimentation pattern at Theopetra is comparable with the trend of the alluviation history in the Plain of Thessaly. Moreover, the observed correlation with major climatic variations, such as the Heinrich events in the Northern Atlantic, could represent the influence of northern latitude climatic forcing on the late Pleistocene climate in central Greece. (C) 2001 John Wiley & Sons, Inc.