The archipelago of Japan contains over 4,000 islands stretching along the Pacific coast of East Asia, with four major islands (sometimes referred to as the Home Islands): Hokkaido, Honshu, Kyushu and Shikoku.he second largest, Hokkaido, is also the northernmost of Japan's islands; while on the other end, Kyushu is the most southwesterly. Shikoku is the smallest and least populous of the four main islands.