When traveling from Kyoto to Tokyo on the Tokaido Shinkansen, the "best" seat is undoubtedly a window seat on the left-hand side (looking toward the direction of travel), which is designated as Seat E in an Ordinary car or Seat D in a Green (First Class) car. This specific side is famous because it provides the iconic, unobstructed view of Mount Fuji as the train passes through the Shizuoka area, approximately 45 minutes before arriving in Tokyo. If you sit on the right-hand side (Seat A), you will mostly see the Pacific coastline and urban industrial areas. It is highly recommended to reserve these "Mt. Fuji side" seats in advance, especially during clear winter or spring mornings when the mountain is most visible. If you are traveling with a large suitcase, you should also try to book the "last row" of seats in the carriage, as these now require a specific reservation for oversized luggage and provide the extra space behind the seat to store your bags securely without blocking the aisle.