To see Mount Fuji while riding the Tokaido Shinkansen (the bullet train line connecting Tokyo to Kyoto and Osaka), you must sit on the correct side of the train and look out at the right moment. If you are traveling Westbound (Tokyo to Kyoto/Osaka), you should reserve a seat on the right side of the train, which is consistently labeled as Seat E in the 3-2 seating configuration. If you are traveling Eastbound (Kyoto/Osaka to Tokyo), the mountain will be on your left side, which corresponds to Seat A. The best viewing window occurs roughly 40 to 50 minutes after leaving Tokyo (near Shin-Fuji Station). It is highly recommended to take a morning train, as Fuji is often shrouded in clouds or haze by the afternoon. On a clear day, the snow-capped peak is visible for several minutes, providing one of the most iconic views in Japan. If you are using a JR Pass or booking at a machine, look for the "Mount Fuji Side" indicator or specifically request the "E" seat for the Tokyo-departure leg of your journey.