The Harding Icefield, the largest in North America, gives birth to glaciers that spill into long, steep, rocky fjords whose quiet coves and bays shelter a dynamic marine life from stormy seas. Covering more than half of Kenai Fjords National Park, it gives a sense of the huge ice sheet that covered Alaska during the last ice age. The Exit Glacier originates from the Icefield, spilling down 3,000 feet to a spot that makes it one of the most accessible glaciers anywhere.