area began about 14,000 years ago and was north of the Canada–US border by 10,000 years ago. The "U"-shaped cross section of the river valleys are a result of that recent glaciation. Uplift and faulting in combination with glaciation have been the dominant processes which have created the tall peaks and deep valleys of the Alpine Lakes Wilderness area. See also Geology of the Pacific Northwest List of peaks of the Alpine Lakes Wilderness Gallery References External links Navaho Peak: weather forecast Climbing Navaho Peak video: YouTube Mountains of Kittitas County, Washington Mountains of Washington (state) Wenatchee National Forest Cascade Range Mountains of Chelan County, Washington North American 2000 m summits