I'm looking to plan a solo 1-2 week trip to Tokyo and surrounding areas. My dates are flexible but I'd like to know the best dates to travel to avoid any busy seasons.
I'd like to catch the Cherry blossoms but if it will be crazy busy that time of year I can avoid it.
My budget will go towards attractions and restaurants as flights/lodging will be covered by points.
I would go in April/May or September/October. August is hot as can be but you can go to some of fireworks shows around the city. They are the best in the world and can be huge. Winter time, if interested, can be great with the skiing. Otherwise cherry blossom season is 1-2 weeks. Agree with the Japan rail pass. You can only buy it OUTSIDE of japan. But it offers great value.
Tokyo can be nice to visit anytime of the year depending on your interests. It's always crazy busy in Tokyo. I've heard the day time population can exceed 30 million so I wouldn't avoid viewing the Cherry blossoms because of the mad crowds! Timing the Cherry blossoms can be a bit tricky however. It varies year-to-year in terms of when and how long the trees are in bloom. Also, you might consider a Japan Rail Pass and visit to Kyoto as well. It's a magical place any time of year but even more so during spring and fall. Have a great trip and soak in the wonderful Japanese hospitality!
As everyone has said, for sure go for cherry blossom season and don't mind the crowds - it's worth it. I think the only effect you'll experience are hotels get booked up faster around that time (so book early if you can), as well as the popular cherry blossom spots being crowded. All the other attractions you'll visit shouldn't be too much affected. If you have two weeks you can probably time it so you catch at least part of the season. I'd try for the last week of march or first week of April.
You mentioned visiting surrounding areas as well - I would strongly recommend taking the train to Kyoto and spend a few days there. It's ridiculously magical in cherry blossom season, I think more-so than Tokyo. The view of Kiyomizu-dera Temple (Kiyomizu dera temple) seemingly floating on clouds of sakura is gorgeous.
Similarly autumn has great views with fall foliage and mild weather (and is another busier tourist season).
While you'll have fun in Tokyo anytime of the year, I would personally avoid summer unless you don't mind very humid and hot weather.... it's usually the time of year people try to get out of the city. I would sweat buckets just between my apartment and train station and always carried around a face towel... spring is a much more comfortable climate, especially for trekking around outside to tourist attractions all day.
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Best time for Cherry Blossom is in spring, between March-May. Japanese will do picnic under the sakura tree. Catch i