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The Alps were covered by a complex ice sheet comprised of various centers of glaciation with occasionally dome-like structures from which huge valley glaciers flowed out. Systems of transection (interconnected valley glaciers) as well characterized the Alps. The ELA across the Alps was between 1000 and 1700 m a.s.l., with a general trend of rising from the margins to the center. At sites farther to the east and south smaller glaciers were present. Glaciers extended onto the northern and southern forelands and formed huge piedmont lobes. Frontal moraines filled the amphitheatres broadly defined by moraines built-up during earlier glaciations. Fields of drumlins were shaped in the footprints of the large piedmont glaciers on the northern flank of the Alps from the Rhone Glacier in the west to the Salzach glacier in the east. The glaciers delivered remarkable volumes of outwash. On the south side of the Alps, huge fans were constructed. In the north, outwash gravels were largely confined to the established river valleys. The timing of the LGM Alpine glacier fluctuations has been studied with radiocarbon dating, luminescence techniques and cosmogenic nuclide surface exposure dating. Expansion of glaciers can be shown to have begun as early as 32.5-30.5 ka cal BP, with glaciers reaching the forelands already by 29 ka cal BP. Most systems exhibit two main advance phases, which in the south have been dated to 26-25 and 23-22 ka cal BP.

Our new dataset from the Rivoli‐Avigliana end‐moraine system, the westernmost amphitheatre of the Italian Alps, provides an important step towards understanding foreland‐reaching glaciations before and during the Last Glacial Maximum (LGM) in the Western Alps. 10Be data from six boulders in pre‐LGM deposits gave ages between 26.8 ± 2.1 and 41.2 ± 1.9 ka. Based on morphological and pedological data, we interpret the oldest age as a minimum age for the glacier advance(s). 10Be results suggest that the LGM occurred in two major steps. During the first at 24.0 ± 1.5 ka, several ridges were constructed demonstrating oscillation of the Dora Riparia glacier snout at the maximum position. Our data demonstrate a significantly larger LGM extent in the Rivoli‐Avigliana amphitheatre than shown on previous maps. The maximum advance was followed by a short re‐advance of the glacier at 19.6 ± 0.9 ka, as recorded by 10Be ages from boulders in lateral positions along the lower Susa Valley. The maximum ice surface during the LGM was at 1000–920 m a.s.l. in the final reach of the valley (560–620 m of elevation above the alluvial plain) and at 620–340 m a.s.l. at the continuous moraines in the amphitheatre.

Our new dataset from the Rivoli-Avigliana end-moraine system, the westernmost amphitheatre of the Italian Alps, provides an important step towards understanding foreland-reaching glaciations before and during the Last Glacial Maximum (LGM) in the Western Alps. 10Be data from six boulders in pre-LGM deposits gave ages between 26.82.1 and 41.21.9 ka. Based on morphological and pedological data, we interpret the oldest age as a minimum age for the glacier advance(s). 10Be results suggest that the LGM occurred in two major steps. During the first at 24.01.5 ka, several ridges were constructed demonstrating oscillation of the Dora Riparia glacier snout at the maximum position. Our data demonstrate a significantly larger LGM extent in the Rivoli- Avigliana amphitheatre than shown on previous maps. The maximum advance was followed by a short re-advance of the glacier at 19.60.9 ka, as recorded by 10Be ages from boulders in lateral positions along the lower Susa Valley. The maximum ice surface during the LGM was at 1000-920m a.s.l. in the final reach of the valley (560- 620m of elevation above the alluvial plain) and at 620-340m a.s.l. at the continuous moraines in the amphitheatre.

Glaciated mountains of the Valle d’Aosta and Piemonte regions are described in relation to the geological, geomorphological and climatic settings of the Western Alps. A comprehensive view of the present-day Alpine regional cryosphere is offered, and links to regional and local examples of its evolution through the Quaternary are provided. Pleistocene moraine amphitheatres (Ivrea and Rivoli-Avigliana) of the piedmont area recall the development stages of Alpine glaciology. Major glaciers (Lys, Miage, Belvedere, Rutor and Sabbione) of the highest peaks of the Western Alps (Mt. Bianco, Mt. Rosa) are analysed for their specific scientific, environmental, cultural and economic importance. The distinctive dynamic nature of the glacial landscape is illustrated by examples of active glacial landforms and related slope instability, whose sensitivity to climate changes can increase hazards and risks.