Mackenzie King Island, 5048 km2, is one of the central islands in the Queen Elizabeth Islands of the Arctic Archipelago. Low-lying, with only occasional points over 300 m, it consists of lowlands and plateaus developed on horizontal or gently folded sedimentary rocks. The general absence of resistant strata is responsible for the lack of salient features. Only on harder sandstone do more prominent landforms, such as the Leffingwell Crags, develop. Material at the surface, being derived from the fine-grained underlying bedrock, is particularly susceptible to solifluction; and Mackenzie King Island has some of the best examples of this process in the Arctic. In 1915, mistaking a strait for a bay, V. Stefansson mapped Borden and Mackenzie King islands as one - an error uncorrected until a 1947 RCAF aerial survey.