To the north is one of the state’s greatest mountain ranges, the Alaska Range. Several peaks in view have elevations greater than 12,000 feet. This range extends in a great arc from Cook Inlet through the Mount McKinley massif (a principal mountain mass) and on to the Canada border, a distance of 650 miles. The Gulkana Glacier, seen from this point, was formed from the buildup of snowfields high in the Alaska Range. Layers of snow accumulated year after year and compacted into ice. As the glacier became heavier, it began to move downslope, scraping and gouging the rock. This action, called glacial erosion, contributed to the rugged, jagged appearance of the Alaska Range and created the long Ushaped valleys seen from the road.
Source: BLM Recreation Guide