瀨戶內海
The Seto Inland Sea was also part of the official Chosendentsushi route, bringing Korean emissaries to the shogunate. After the Meiji Restoration, the coastal cities along the Seto Inland Sea were rapidly industrialized. One of the headquarters of the Japanese Navy was built in the town of Kure. Since the Meiji period, development of land transport has been reducing the importance of the Seto Inland Sea as a transport line. Remarkable land transportation innovations include the San'yō Main Railroad Line in Honshū and the Yosan Main Railroad Line in Shikoku (both completed before World War II) and three series of bridges connecting Honshū and Shikoku (completed in the late 20th century). The Seto Inland Sea is still used, however, by an international cargo transport line and several local transport lines connecting Honshū with Shikoku and Kyūshū.