Did 3 weeks in Japan, 1 week in Tokyo and 2 weeks in Osaka.
Great trip. Amazing food. Language can be challenging at times when you get away from the cities.
Suggestions
Tokyo- get up early and go to the Tsukiji Fish Market. You’ll see things you didn’t know existed. Eat in one of the local places that caters to the market workers. Also a Greta place to buy a sushi knife. Lot’s of blade makers in the area, you don’t need to do a tour you can just walk around, The tuna auction is interesting to watch
Shibuya Crossing just a mass of neon and humanity but fun to walk around
Obviously hit the major temples as well.
Food- you can’t go wrong. If you like sushi maybe do one formal dinner other than that I’d suggest ramen houses and izikayas. These are tiny little hole in the wall places but the food is amazing.
Yakiniku- grill your own meats
Also worth trying okonomiyaki - type of savory pancake, very good
Tako balls- you’ll see street carts selling these. Little deep fried balls of dough with a small piece of octopus in the middle. Sounds odd but very good.
I assume you’re taking the bullet train to Osaka. That’s a cool ride.
While in Osaka take a day trip to Nara, cool town with deer walking all over. Navigating the trains can be challenging outside the cities because everything is in kanji but someone will help you if you get stuck.
A buddy married a Japanese girl and their close friend owns a restaurant in Osaka. I’ll try and get the name. If you are an adventurous eater that is the place, They serve whale, horse etc along with more standard stuff, They have a miso, pork, mushroom dish that’s one of the best things I’ve ever eaten.
Other things worth doing
Onsen- Japanese bathhouse. If you have tattoos you will not be able to go to the mainstream ones you’ll have to do the ones that allow Yakusa,
In Japan you see a guy with tattoos 95% chance they are Yakusa
If you see a license plate with repeating #’s or all the same #. Guy is probably Yakusa.
Another odd thing you’ll see is salarymen getting absolutely annihilated drunk with their coworkers, Some will get so wasted they pass out on the street. Saw one guy passed out with his wallet and keys on his chest and people just let him be.
Any Q’s let me know.