 The climate is generally humid subtropical in western Japan and humid continental in the north.Honshu is connected to the islands of Hokkaido, Kyushu and Shikoku by tunnels and bridges.Three bridge systems have been built across the islands of the Inland Sea between Honshu and Shikoku (Akashi Kaikyō Bridge and the Ōnaruto Bridge; Shin-Onomichi Bridge, Innoshima Bridge, Ikuchi Bridge, Tatara Bridge, Ōmishima Bridge, Hakata–Ōshima Bridge, and the Kurushima-Kaikyō Bridge; Shimotsui-Seto Bridge, Hitsuishijima Bridge, Iwakurojima Bridge, Yoshima Bridge, Kita Bisan-Seto Bridge, and the Minami Bisan-Seto Bridge), the Seikan Tunnel connects Honshu with Hokkaido, and the Kanmonkyo Bridge and Kanmon Tunnel connects Honshu with Kyushu.