Hi. I suggest you visit the Toyosu Fish Market in the early morning where the tuna auction is lively. The tuna auction takes place from about 5:30am to 6:30am. If you’re happy watching from the upper-floor observation windows, you don’t need to sign up beforehand; just be there as early as possible and try to grab a good spot. The gallery opens to visitors from 5am and auction prep is already in full swing at that hour. However, the gallery is the B-grade option for viewing the tuna auction, and you might leave having seen nothing but a bunch of people’s heads. The Toyosu tuna auction can also be viewed from a special deck on the lower floor. Access to this deck is by application only, with applications open for about seven days each month, for a spot the following month.
If you aren’t set on the auction and just want to see some market activity, you don’t have to be up at the crack of dawn; you just need to be there before 8am. If you simply want to eat some sushi, you can go anytime—and skip the tuna/wholesale fish market area.