Turret trucks careening around corners, workers unloading boxes of glistening scales and tentacles, tuna carvers wielding samurai swords. All happening while Tokyo sleeps.

Tsukiji Market holds a storied place among international visitors and chefs in Tokyo. It is the world’s largest wholesale seafood market, sprawling across 23 hectares or about 55 American football fields. Over 2,000 tons of product moves through these stalls every day, ranging from tiny anchovies and smelt to hulking tunas and cuts of whale.

In recent years, the frozen bluefin tuna auction has become a popular attraction for tourists, drawing large crowds who have sometimes been disruptive. In response, the Tokyo Metropolitan Government (TMG) banned the admittance of visitors for a while, then settled on allowing the first 120 people to view the auction from a designated area. Visitors are admitted beginning at 5 am, and people start lining up even earlier than that.

But don’t go to Tsukiji just to wait in line for the frozen tuna auction; there’s plenty of other sights and stories to learn. I was lucky to come across Naoto Nakamura, a tour guide who worked in the seafood industry for 12 years and may well be Tokyo’s leading expert on the market’s history. At 3 am, we gathered just outside of the market and Nakamura-san explained the ground rules: no photographs with flash, no standing in heavily trafficked areas, and if TMG security guards approach, simply say that you’re shopping and move if asked.

As you approach the market’s periphery, paper lanterns at Namiyoke Inari Shrine glow quietly in the night. Many of the names inscribed are prominent Japanese companies or seafood dealers. Here, the left-most lantern is for Shochiku, a Kabuki theater producer and movie studio.

While the shrine is certainly not one of Japan’s largest or grandest, it plays an important role as a protector of the market and its entrepreneurs. Inside the small courtyard, carved stone monuments have been placed by various traders and merchant groups to bring good fortune to their industries.

At this time, the outer rings of the market are just awakening, and sellers of pickles, omelet cakes, seaweed and knives begin to unveil their merchandise. The outer market was once exclusively for “amateur” buyers, while the inner market was for professional wholesalers and businesses, but now the distinctions are less clear.

Once you pass into the inner market, bright lights and hurried drivers keep you alert and on your toes. At the frozen bluefin tuna auction, tuna are unloaded by throwing them off the trucks onto tires, where they sometimes bounce and skitter onto the pavement. They will be dragged with hand hooks onto the auction floor.

To examine the tuna’s quality, a section of the tail will be cut. Only licensed traders are allowed to participate in the auctions, and a limited number of tuna are released each day by the auction houses. This ensures that the price of tuna remains relatively stable day to day.

The frozen tuna come from all over the world, and are frozen onboard ships as soon as they are caught to limit spoilage. These ships are typically out at sea for 1-2 years at a time, so the tuna may have been caught many months before being auctioned. There is a parallel auction for fresh tuna, which mostly includes tuna caught near Japanese waters.

Outside of the auction halls, hundreds of middlemen run stalls to deal their products to chefs, restaurants and other businesses. It may look chaotic, but the aisles are numbered and grouped according to the products sold. Here, you can find iridescent Japanese tiger shrimp, live scallops, geoduck, ark shells and many more unrecognizable seafoods.

The traders at Tsukiji have a reputation for being hot-tempered, and you certainly don’t want to pick a fight with anyone carrying sharp knives. Whole tuna are first sectioned off with bandsaws, then master carvers use long swords to further break down the tuna.

We circled back into the fresh fish area, where glistening bodies were neatly packed on beds of ice. On that day, the fresh fish auction sold about 100 cases of fish, a decline from past years. These days, it’s mostly high value fish that are brought to Tsukiji for auction. The lower priced seafood is sent directly to supermarkets through their proprietary supply chains.

One market that is flourishing at Tsukiji is live seafood. In the past, the Japanese felt that live fish were not as high in quality because the fish became stressed in the tanks. So, live fish was mostly confined to the Chinese and Korean markets. However, about a decade ago, Tsukiji began investing in generators and oxygenation systems to reduce stress on captive fish, and subsequently, the market for live seafood took off. Above, you see a tank of fugu blowfish, infamous for containing a neurotoxin that can paralyze or kill the diner if prepared improperly.

For our last stop, we peeked in on the uni (sea urchin) auction. In a room reminiscent of a high school, middlemen took notes and used hand signals to place bids. The smell of cigarette smoke filled the air, despite an abundance of “no smoking” signs. You can see in this photo that two auctioneers are standing on raised platforms, conducting two different auctions simultaneously. Apparently this is not confusing because buyers typically buy the same types of products from the same auction houses, so it’s clear to the auctioneer if you are bidding on the left or right side.

Visitors to Tsukiji traditionally grab a sushi breakfast after their tour. Both Sushi Dai and Sushi Daiwa in building #6 are well-known, and will have hours-long lines as early as 6 am. If you don’t want to wait, all of the restaurants around Tsukiji have excellent seafood, and your options will be even wider if you’re open to non-sushi restaurants. I opted for a seafood rice bowl with octopus, scallop, salmon, roe, sea urchin and squid to cap off the morning.

Tsukiji Market is slated for relocation in 2016, and is one of the few urban wholesale markets that is still easily accessible for outsiders and located near the city center. (In contrast, Rungis Market outside of Paris is closed only to registered buyers and sellers.) Visit this important cultural landmark while you can! Or if you’d like to visit from your armchair, tour guide Nakamura-san has also written a very entertaining collection of short stories about the market, Free Jazz at the Tsukiji Fish Market, where you can learn the market’s inner workings and his fight to preserve the original location.