Visit places such as shinjuku. We used to book a venue called “the loft” which in true Japanese style was 2 floors underground. If you see a record shop there called “vinyl” do me a favour and take a photo as I worked for them for 12 years.
The giant Buddha is actually worth travelling to see.
Everyone I met there was super friendly when I used to go there. However, there is very open naked racism towards certain demographics. My old boss used to come out with some truly shocking things. It cost me a fortune to bail him out of police custody when someone tried to be friendly and asked him if he was Korean.
Being English is cool. Being Welsh is super-cool.
Subways are a potential nightmare. Their underground trains run on the same tracks as long distance trains. I discovered this via a 200 mile detour whilst trying to travel one stop.
Not sure if it’s still the same but in the 90s everywhere was extremely advanced in terms of access for the disabled. This particularly applied to visual disabilities. Bit of a legacy from the two bombs.
Again it may have changed but toast was a real novelty last time I went. Served at breakfast, you got sliced bread about 2 inches thick. Mothers pride style bread and brown bread was white bread with dye added. Rice and egg for breakfast loses its appeal after you have it a few times.
Food is generally very fresh. Almost impossible to be vegetarian there though as they seem to view it as a challenge to stick something fish based on your plate. The still moving octopus was a bit too rare for me.
If you travel outside of Tokyo literally everywhere is “the 7th most important place in Japan” . Some of the islands are really cool. Lots of people outside of the cities will want to video you. School kids will run up and ask you to say stuff so they can translate it in school. Contra to popular opinion lots of Japanese people are very friendly to strangers. I used to have people offering me lifts in their cars if i looked lost.
It’s still a novelty for some people to be impressed with height. If you are reasonably tall prepare to learn the Japanese for “tall” and “giant” pretty quickly.
Spring time is a genuinely great time to go. In the summer it is oppressively hot and close.
Budget far more than you expect. It really is like living in a nightclub in terms of prices. The vending machines are cool.
Not sure if they still have wax mock ups of food in restaurants but if they do it makes things do much easier to order.
Again this may well have changed but there is lots of BDSM stuff in regular magazines. During the late 90s my boss was delighted that laws were changed to allow them to show public hair but only “domestic not “imported”.

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Again it may well have gone but you used to be able to buy an unlimited train pass for foreign tourists. This would save a fortune (but didn’t cover the bullet trains)
Don’t go through customs drunk or try to be a wise-ass I’ve had several bands turned away at the airport. There also used t9 be a leaving tax at the airport which was a pain if you had spent all your local currency’.
Have a great time there. I need to go there with my family in the near future