To get the most iconic view of Mount Fuji while traveling on the Tokaido Shinkansen between Tokyo and Osaka (or Kyoto), you should always aim for the "E" seats in an Ordinary car or the "D" seats in a Green (First Class) car. If you are traveling West (Tokyo to Osaka), these seats are on the right-hand side of the train. If you are traveling East (Osaka to Tokyo), they are on the left-hand side. The mountain appears roughly 40 to 45 minutes after leaving Tokyo Station, shortly after the train passes through the Atami and Mishima areas. The "prime time" for viewing is the few minutes surrounding Shin-Fuji Station, where the mountain fills the window. Because the Shinkansen seats are rotated 180 degrees at the terminal to face the direction of travel, the "E" seat is consistently the "Fuji-side" seat regardless of whether you are heading north or south. It is highly recommended to book these specific seats in advance via the Smart-EX app or at a ticket machine, as they are the first to be reserved by savvy travelers.