Five airship hangars.
Mind you, the Imperial Russian Air Service had smaller airships than the U.S. Navy, so the hangars aren't quite as gigantic as the one at Moffett Field. Still, you could put a football field inside each of these things with plenty of room to spare. And the market doesn't actually fit inside the five of them, but spills out all around.
One of the hangars is devoted to fish, one to produce, one is a butcher market, one has lots of delicatessen stalls. The fifth is divided into sections including baked goods and nuts. Outside, there are sections for flowers, clothes, shoes, household goods, and more produce. People say one can get lost here although I didn't find it very confusing. Just big. Very big.
I rather wished I had a self-catering flat, or at least a kitchen, to take advantage of all this food.
The market is, broadly speaking, open from 0700 to 1700 daily, although individual kiosks may open earlier or later. The market takes up a lot of space behind the train station and behind the bus station. To say, "You can't miss it" is something of an understatement, as you can see the airship hangars from anywhere nearby.