Lake Nahuel Huapi is the first stage of the busiest of the routes used by the Indians. It came from the lower Santa Cruz, went up the Rio Chico, and from there northward followed the foot of the Cordillera. D'Orbigny was told about it: "All the Indians who live near the Andes go along the eastern foot of the mountains in their journeys, because they find water there, whereas they would find none if they went by the coast; in that way they travel from the Straits of Magellan to the Rio Negro." The Indian track only left the sub-Andean depression between the Rio Chico and Lake Buenos Aires, in the district where the high basalt _mesetias_ extend as far as the Cordillera, and on the Pampa of the Sanguerr. From Lake Nahuel Huapi the Indians of the south descended the Limay and the Rio Negro, and reached the island of Choele Choel, some 230 miles above Carmen, where they met the Aucas and Puelches. There they exchanged their _guanacos_ hides for woollen fabrics made by the Aucas. Choele Choel was the only large, purely indigenous market; the whites never visited it. Geographical reasons fixed the site of this market of the nomads. In the latitude of Choele Choel the Rio Negro approaches the Colorado and the archipelago of the Sierras of the southern Pampa, which mark so many stages on the routes from the Pampa to the Andes. To the south the coast-route, less exposed to snow than the sub-Andean track, began from Choele Choel. The Indians followed this to reach the Gulf of San Jorge and the Santa Cruz in winter, during the rainy season. Darwin notes the importance of the site and the ford of Choele Choel. Villarino had suspected it, and had, as early as 1782, pleaded for the building of a fort there. By holding this point, he said, they could prevent the tribes from attacking Buenos Aires, or from approaching the Patagonian coast in the district of San Jose.[61] [61] _Informe de D. Basilio Villarino a Fr. de Viedma_, Coll. de Angelis, v. As far back as we can go, the life of the Indians seems to have been deeply influenced by their relations with the whites. The Aucas brought to Choele Choel, not only the products of their industry, but also objects stolen or bought from the Christians on the Pampa. The report of Musters, who followed a Tehuelche tribe from Santa Cruz to the country of the Manzanas ("land of apples"), shows clearly that the attraction of the Nahuel Huapi region for the Indians was less due to its natural resources than to the presence of the Chilean settlements at Valdivia, from which came across the passes of the Cordillera certain quantities of brandy.