You might say there's something fishy about our Geo Quiz. We're looking for the name of the the biggest wholesale fish market in the world. It's located in Asia and it dates back to the 16th century, when Japan's military rulers wanted to ensure they had a steady supply of fish. Nowadays this market handles more than 700 tons of seafood per year…from the tiniest sardines up to the giant swordfish in demand by sushi chefs. There's caviar and seaweed for sale at this market that opens each morning before dawn. That's when the blue fin tuna are auctioned off to bidders wearing rubber boots and baseball hats for thousands of dollars. It's worth noting that many of the tuna species on sale at the Tsukiji Market are badly over-fished. Bluefin tuna in particular are near collapse, according to the International Union for the Conservation of Nature. Here's a video from the daily pre-dawn tuna auction: The Tsukiji Fish Market in central Tokyo opens for business each morning before the sun comes up. Tons and tons of frozen tuna are unloaded, packed in ice and and spread out for auction. Steve Dolinksy recently toured inside the market, and sent us this postcard from the biggest wholesale fish market in the world.