At the junction of the Himalayas with other large mountain systems such as the Karakoram, Tian Shan, Kunlun and Hindu Kush lies the Pamir Mountains, including mountains exceeding 7000 m in its northernmost fringe. This is the case of the Trans-Alay Range, where Lenin Peak (7134 m) is located. This communication focuses on its northern slope, from the glaciated environments until the Alay valley floor, a wide semi-arid valley running E-W at altitudes between 2500 and 3000 m. In August 2017 we visited the area with the objective of mapping the main geomorphological features and collecting samples for terrestrial cosmogenic dating in order to reconstruct glacial oscillations in the area during the Late Quaternary. In this preliminary approach, we introduce the main geomorphological units observed in the area from the valley floor to the highest lands:

(1)   Valley floor (2900 to 3330 m): this area must have been ice-free during the Last Glaciation and is currently being intensely shaped by fluvioglacial processes, namely by large alluvial fans reworked by aeolian activity. We also observed a sequence of fluvial terraces generated both by the Alay river as well as by the tributaries.

(2)   Hummocky terrain (3330 to 3500 m): During the Late Quaternary glaciers reached the foot of the mountain and spread across the flat environment forming two main moraine systems intensely reworked by postglacial dynamics. The hilly terrain made of steep-sided ridges and conical hills includes also tens of ephemeral lagoons and (semi)permanent lakes.

(3)   U-shaped glacial valley (3500 to 3800 m). The main glacial valley includes a sedimentary cover tens of meters thick composed of glacial till that is being eroded by mass movements and alluvial processes, which also favour the development of several river terraces down-valleys. Two moraine systems are distributed near the glacial front at 3730 and 3780 m, respectively.

(4)   Mountain valleys (up to 4600 to 4800 m). Several mountain ridges are distributed at both sides of the main valley forming both single U-shaped and hanging glacial valleys. The highest mountains hold cirque and small alpine glaciers with fronts reaching elevations of 3700-3800 m. The non-glaciated environments are affected by intense periglacial processes, with widespread solifluction, landslides, talus cones, debris flows, etc., as well as evidence of permafrost conditions, as revealed by the presence of rock glaciers and protalus lobes.

(5)   Glaciers. The entire northern wall of the mountain is fully glaciated. Depending on topographical conditions, the lower limit of the glaciated environment is located at ca. 3800-4500 m, where the high sediment supply conditions the existence of a debris-covered glacier. The glacial front is now located at the confluence of the two main alpine glaciers at 3810 m.

The results of the samples which are being now processed through cosmogenic dating will provide the chronological framework for glacial stages that have shaped the area surrounding the Lenin Peak since the Last Glacial Maximum.