Age and the Great Glaciation. It is divided into two additional interstadials, the so-called Double Holstein Event of Meikirch (doppelte Holstein-Vorkommen von Meikirch), which is not identical, however, with the Holstein interglacial. During the period of maximum glaciation, ancient man (Homo heidelbergensis – later the Neanderthals) retreated behind the permafrost boundary and, in the warmer periods, spread beyond it to the north and northeast. Not until the Weichsel-Würm ice age did modern Cro-Magnon man settle these regions, in about 40,000 BC. Sequence and extent of the Riss glaciation At the beginning of the Riss ice age almost all of today's river valleys were created. The glaciation of the Alps, even before the Holstein interglacial and towards the end of the major glaciations, resulted in glaciers advancing in several phases far into the Alpine Foreland, further than all other known ice sheet advances, and the main glaciers had established themselves along today's river valleys. During the Riss, glaciers advanced into the Bavarian and Austrian Alpine Foreland probably four times. The first two advances have not been confirmed with certainty because they are overlaid by the two stadials at the end of the Riss glaciation that extended well to the north. The ice sheet advances of the cold period were mostly well beyond the glacial lake of the previous ice sheet. In most areas, the Riss terminal moraines have formed as low embankments, for example in the area of the Inn Glacier, the Isar-Loisach Glacier, the Iller Glacier, and in the area of the western Rhine Glacier. In the type region in Biberach there is a clear, but rather atypical double moraine ridge, also atypical is the double terrace here, which is probably due to heavy erosion as the meltwater runoff moved from the and Altmühl valley into the present day Danube valley, a process that took place during the Riss glaciation. The double ridge of the type region (Doppelwallriß, with an outer and inner ridge) is a result of two superimposed sequences of glacial deposits which indicates that the Riss was subdivided into at least two stadials. In the west the Rhône Glacier covered large parts of the Swiss Plateau and reached as far north as the northern Folded Jura and as far south as Lyon. To the northeast, it transitioned without any sharp demarcation into the Linth Glacier and Reuss - Aare Glacier; only the Napf area remaining ice-free. Further