Discontinuous change of denudation basis in the uprising mountains of Tien-Shan leads to the formation of terrace sequences and contiguous slopes common to large territory. Carst caves "Obi-Rakhmat" and "Pal'tau" are located between levels of second and third terraces, what unambiguously evidences that they were already used by human after cutting of the river into the surface of third and accumulation of the second terraces. If we suppose that paleolithic settlements gravitated to river channel, the second terrace, having large extension in the upper valley, may be considered as the most perspective area for discovering the paleolithic artefacts.