In the arctic north polar bears and musk ox live in a treeless, wind-blown ice-cold tundra, in Prince William Sound in the central south countless majestic glaciers calve into the sea, in the south west huge extremely active volcanoes rise into the sky and in the mild south east the last cold rainforests on earth thrive . Mount Mc Kinley, the Denali (the great), as the native Athabasque Indians call it, rises above everything, the highest mountain in North America.