The main islands of Japan are Honshu, Hokkaido, Kyushu, and Shikoku. Honshu is the largest and houses key cities such as Tokyo and Osaka. Hokkaido, located to the north, is known for its natural landscapes and colder climate. Kyushu, the third-largest island, features a more temperate climate and active volcanoes. Shikoku, the smallest main island, is famous for its pilgrimage routes and rural landscapes. Together, these islands contribute to Japan's cultural diversity and geographical variety.