National Route 1 is a major highway on the island of Honshū in Japan. It connects Chūō, Tokyo in the Kantō region with the city of Osaka, Osaka Prefecture in the Kansai region, passing through the Chūbu region en route. It follows the old Tōkaidō westward from Tokyo to Kyoto, and the old Kyo Kaidō from there to Osaka. Wikipedia