At the lower levels, the tundra holds many ponds and low shrubs including willow, blueberry and dwarf birch. The wildflowers of the park provide a spectacular carpet of many colors. The geology of Denali is fascinating. Eight long glacial troughs radiate from the Cathedral Spires, many of them with head walls more than a mile deep.
Granite domes look down on wide plains.
The ecosystem supports a wide range of wildlife, including moose, caribou, wolves, grizzly bears, Dall sheep, wolverines and more than 150 species of birds, many of them waterfowl. The negative effects of too much traffic on the Park Road leading to the major camping and resort area has caused the National Park Service to limit traffic through the park. Shuttle buses provide the preferred form of transport through the park areas and visi tors are required to park their vehicles in one spot and leave them there. Mountain climbers have challenged Mt. McKinley since 1903. The mountain is shrouded by clouds and mist two days out of three dur ing the summer months.