The first picture shows a handaxe found at Oudry (Saône-et-Loire) during the 19th century ,most probably from the MTA.
People living in the 21th century have enormous difficulties to imagine river landscapes not modified by men. In general, glacial rivers were perhaps some of the most physically diverse ecosystems on earth and characterized by tremendous habitat complexity that shifted in space and time at a wide variety of scales (look at the last picture).
Glacial rivers typically adopt one or both of two general channel forms: braided or anastomosed, while meandering rivers seem to be connected with interstadial and interglacial conditions. Braided rivers are characterized by relatively high stream power, high rates of erosion, deposition, and channel change. Anastomosing rivers are show lower channel slope gradients, and perhaps higher rates of deposition. Meanders forms, when moving water in a stream erodes the outer banks and widens its valley, and the inner part of the river has less energy and deposits silt. Worldwide shifts from braided to meandering patterns near the end of the Late Pleistocene and marine Oxygen Isotope Stage 2 (MIS 2; 29–11 k.a. cal. BP) are well documented.
Rivers can play a role as mobility and communication vectors but also act as barriers and their role varies considerably over time. The Danube valley and the Rhine are well known examples for the impact that large-scale river systems had on the spatial organization of the Central European Magdalenian.
The Rhône–Saône Corridor represents a major fluvial route in Europe. It is linked to the upper valley of the Loire in the West, and in the East to the Rhine via the Meuse. While, the Rhône/Saône axis was fast becoming the most important trade route in pre-industrial Europe and provided access to the center of Western Europe through the Mediterranean region, it was was a barrier during the onset of the Last Glacial Maximum. This can be demonstrated by the sharp separation of the Solutrean technocomplex from the Early Epigravettian further east. It seems that periglacial permafrost conditions in the Rhône Valley, with successive freezing and flooding events, hampered communication between human groups east and west of its banks.
Burgundy, located between northern and southern Europe and has always been a gateway between Western and Central /Northern Europe .Since the second half of the 19th century, Southern Burgundy has constituted as an important region for Paleolithic research. It contains important remains from the Middle Paleolithic, the Châtelperronien, the Aurignacian and the Gravettian. While the Saône and Doubs constituted the eastern border of the Châtelperronian and Solutrean interaction sphere, there seem to be links between the Aurignacian and early Gravettian of Burgundy and S/W-Germany.
It seems that the Rhône/Saône axis was rather a gate to Middle Europe than a barrier during the long time span of the Middle Paleolithic (300-40 k.a.). KMG elements are found in the Northern Burgundy in the context of the OIS 5 (Champlost), while other sites with KMG- affinities could be from MIS3, like several Middle Paleolithic sites in Dept. Saone-et-Loire that contain classic Keilmesser (bifacially backed knifes with or without para-burin blows) like the Grotte de la Mere Grand a Rully; La Roche a Saint-Martin-sous-Montaigu; the Grotte de Teux Blancs a Saint-Denis-de-Vaux; the Grottos de la Verpilliere I and II, the latter have been re-excavated during the last years.
On the other hand we find classic MTA-ensembles near Charolles. In the vicinity of Charolles, numerous surface stations were discovered, most of them situated on hill ridges; among the surface material, the Paleolithic dominates largely. In the Charolles area there are several Middle Paleolithic scatters: “Les Tyrs” and “Brèche”, Champlecy (“la Grelesse”) and Oudry.
Oudry, a site already known since the 19th century in contrast, shows the characteristic lithic elements of the MTA: Cordiform bifaces and backed knifes (but mixed with some Quina scrapers).
For your imagination: The last picture shows a braided drainage pattern near the junction of the Yukon River and Koyukuk River under glacial conditions (Wikipedia Commons):
Suggested Reading: The paper of the year!- a nice synthesis of theory and big data
Shumon T Hussain, & Harald Floss: Streams as Entanglement of Nature and Culture: European Upper Paleolithic River Systems and Their Role as Features of Spatial Organization (via researchgate)