Iceberg Lake may be one of the most popular destinations in all of Glacier National Park, but this view of it is quite rare. This picture was taken from near the summit of the formidable Mount Wilbur. Mount Wilbur is one of the most difficult peaks to climb in the park, with most routes requiring rock-climbing equipment and all routes including exposure to great heights. The Iceberg Lake cirque consists of 3,000 foot walls on three sides of the lake, the southern wall being Mount Wilbur, with the Ptarmigan Wall forming the western and northern sides, Iceberg Peak sitting atop the northern portion of the Ptarmigan Wall. Icebergs persist deep into the summer and often into the fall due to the lack of direct sunlight caused by these enormous walls.