Tsuki isn’t built for early morning risers, though it seems like it when you’re struggling from sleep well before sunrise. The seafood branch of the central wholesale markets supplies all of Tokyo with fresh fish, and the five a.m. tuna auctions are really taking place in the middle of the night shift's working day. Tsukiji is a working world, built for auctioneers and wholesalers. It’s not meant for tourists, and, knowing this, tourists are all the more eager to go.

The air is chill that early in the morning any time of year, and in November I was thankful for a hot can of vending machine coffee to warm my hands and open my eyes. We’d missed the first train, and, consequently the tuna auction. Relief mixed with disappointment: the auctions are famously exciting, but just as famously tourists aren’t really welcome. I was secretly glad to be running late.

At six a.m., the market bustled. Narrow alleys were packed with Styrofoam crates of fish, as if some great tide had washed half the contents of the Pacific up onto the shores of Tokyo Bay. There were scallops and snapper and eels and octopus, squid and prawns and mussels. Crates of sea urchin roe were stacked head-high on wholesaler’s counters. Fresh tuna, straight from the auction, was pushed past on two wheeled carts on its way to be cut for sale, and was cut with metre-long knives while we watched. Frozen tuna were cut with bandsaws by young men in rubber aprons. Everyone wore wellies. Over everything was the constant murmur of voices: people talking into telephones and mobile phones, wholesalers talking to retailers. Deals were being made. By evening all that fish would be on Tokyo’s tables.

By breakfast time I had lost my appetite. Tomorrow again the catch would come in, the fish would go to auction, and everything would happen all over again. Tomorrow, and every day but Sunday and sometimes Wednesday, when the market is closed. There is something shocking about the idea of all that fish simply and completely vanishing into the metropolis. At Tsukiji you can see, first hand, how the oceans are emptying.

All the same, I ate. In one of the tiny sushi shops that dot the outer market we sat at the counter and drank a hurried cup of scalding green tea with our morning sushi. It’s a busy place, after all.