AbstractThe paper describes periglacial structures and landforms developed under Pleistocene coldclimate conditions in western Czechoslovakia. The thickness of Upper Pleistocene permafrost in this territory may have been between 50 and 250 m. Climatically controlled valley asymmetry developed because of different cryogenic processes on opposite valley sides and lateral stream migration (mainly due to thermal erosion). In some cases cryopediment‐like foot‐slopes developed due to down‐wearing of river terraces and/or to the combined effect of down‐wearing and back