Archaeological sites of the A.A. Inostrantsev (Late Mesolithic - early iron age) was found in the 1878 during the construction of canals on the southern coast of lake Ladoga. Their cultural layer is now below the current water level and buried under the multimeter strata of sediments of the Late Holocene Ladoga transgression. Palaeogeographic conditions of existence and the modern geological context of these sites are the classical, oldest and still un-solved problem of Quaternary Geology of the North-West of Russia. It's established that the geological structure of the Quaternary strata in the area of sites has a number of fundamental features on the basis of detailed geological, geomorphological, litho-, palino- and chronostratigraphic investigation of late- and post-glacial deposits. Among them it should be noted: (1) the basin and subaeral Medium-Late Holocene deposits of the same age are located at the same height; (2) time stretching of the final (regressive) phase of the Ladoga transgression in the lower reaches of the Volkhov river; (3) archaeological sites of reticular (textile) ceramics in the lower reaches of the rivers Volkhov and Syas' are located below synchronous water level; (4) the asymmetry of the structure of the left and right banks of the Volkhov - including thickness decreasing Early Holocene member until its complete washout in the territory East of the Volkhov, youth and anomalous thickness of the sands with discoveries of A. Inostrantsev on the track channels, as well as the emergence in the late Holocene accommodation space and the formation of lagoon, where it accumulated a powerful strata of the Ladoga transgression sediments. These features control the spread of the findings of the A. Inostrantsev's discoveries and, apparently, the differentiated sin- and postsedimentation submergence of the Volkhov-Syas' interfluve in the Late Holocene (it's amplitude increases in the Northern direction).