The land consists largely of rolling plains along with some hills. The plains are of varied kinds, including coastal plains and drumlinized plains (areas dominated by cigar-shaped mounds whose alignment marks the path of former glaciers). Some of the drumlins along the upper Back River are nearly flat and others west of Chantrey Inlet are among the most dramatic in Canada. Besides deposits of moraine, there are large areas of marine deposits. Throughout the area some bedrock may be exposed. Soils are frozen and only thaw to shallow to medium depths in the summer. Frost boils and patterned ground attest to the action of frost. The underlying frozen ground acts as a barrier and prevents soils from readily draining. Waterlogged and damp soils are common. Small lakes are numerous and are important for waterfowl and fish habitat. Easterly flowing rivers such as the Thelon and Back have played an important part in history and are currently used for canoeing and wilderness adventures.