Geomorphological research in the Tiksi area, northern Yakutia (Sakha republic), has revealed evidence for a former maritime ice sheet centered on the East Siberian shelf. Fresh‐looking U‐shaped valleys, giant grooves, rock drumlins, crag‐and‐tails, striated boulders, and impressive systems of glaciotectonic ridges coupled with rock basins ("hill‐and‐hollow pairs") were found in the area; all attest to past ice movement in a landward direction, i.e., NE‐SW. The start of lacustrine sedimentation in the rock basins was radiocarbon‐dated using AMS at 6450 ± 110, 6870 ± 80, and 8500 ± 160 years B.P. Additional evidence for ice marginal positions and ice‐flow directions is provided by the oriented lakes of the Yana‐Indigirka Lowland.