I have heard about Tokyo fish market (Tsukiji) so much that i had to go visit it since it was just a walking distance from our hotel.
What i know about it is that i have to be there not later than at 4:30 am so on a Monday night i slept very early so i can wake up before 4:30 am the next day and so i did.
Tokyo is considered one of the most safest Metropolitan in the world so walking around before the break of dawn was no problem and it was a jolly nice walk.
When i arrived there the ships had already ducked at the Harper and started loading off the catch of the day and people where going around like it was a beehive, you see food a big at the oriental 
But it seemed that i made a mistake entering from a wrong gate where i found my self right at the hart of the fish market which is a prohibited area for tourist but i’m glad that i wondered there see the market but then the police caught me :/ and they escorted me out of the prohibited area and told me go to the tourist office! i didn’t know that Tsukiji had a tourist office!? when i when there it was around 5 something am and the officer told me come tomorrow before 4:30 am so i can get a ticket to enter the fish betting 
i didn’t know i missed it ggggggg! but i didn’t, waking up 4:00 am one time during a trip is enough for me.
If its defecation for you to wake up very early in the day to go to Tsukiji fish market its OK its not a must see attraction although i do recommend going there because its an off the beat attraction location.
