ABSTRACTThe extensive occurrence of glacier ice cores to landforms and deposits of the Neoglacial and Little Ice Age periods in the St. Elias Mountains of the southwest Yukon is described. These glacier ice cores were produced during active glaciation and have been preserved, in locations such as the Donjek Glacier moraine, for over 500 years. Incorporation of ice in landforms and deposits occurs during glacier surges, glacier advance or glacier backwasting as well as during stagnation of the glacier. The primary terrain ranges from sequences of moraines, providing a detailed record of glacier fluctuations, to ice contact landforms. The degradation of the ice-cored terrain is controlled by hydrological and glaciological processes, which expose the ice core, rather than by melt beneath the surficial materials.