The Fish market is the best part in Agora. Wear shoes, not flip-flops. The ground is kind of wet and fishy. Wander around and look at all the fish, some fresh, some frozen, and listen to the voices of the merchants as they call out their prices. For some reason the pigs feet are in with the fish and I have not understood that but if its OK with the fish then it is OK with me. Any fish you can find in the Aegean and even some imported frm as far away as China, Portugal and North Africa are here. You will know what fish are in season and what to order in the restaurants after a short walk through the fish market because those will be the fish that there will be the most of and will drop in price as the day gets later. I guarantee you will be impressed by some of the creatures of the deep on display. You will also be surprised at the variety and the noise. Fish venders know how to shout. Surrounding the fish market on three sides is the meat market and across the street are the fruits and vegetables. The weirdest animals are found in the meat section closest to Omonia, though this depends on the season. I have seen giant woolly animals that looked like either a giant wild boar or a mastodon.