Honshu (Japanese: 本州, Hepburn: Honshū; pronounced [hoꜜɰ̃.ɕɯː] ; lit. 'main province'), historically known as Akitsushima (秋津島; lit. 'dragonfly island'), is the largest of Japan's four main islands. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the seventh-largest island in the world, and the second-most populous after the Indonesian island of Java.
Honshu had a population of 104 million as of 2017, constituting 81.3% of the entire population of Japan, and mostly concentrated in the coastal areas and plains. Approximately 30% of the total population resides in the Greater Tokyo Area on the Kantō Plain. As the historical center of Japanese cultural and political power, the island includes several past Japanese capitals, including Kyoto, Nara, and Kamakura. Much of the island's southern shore forms part of the Taiheiyō Belt, a megalopolis that spans several of the Japanese islands. Honshu also contains Japan's highest mountain, Mount Fuji, and its largest lake, Lake Biwa.