Wheat was scarce in Greece, so both players must secure other goods supply and the route to five markets in order to trade them for wheat. Each territory may give you different amount of wood, metal, wine, olive oil, silver and some wheat; these two last ones are hard to get but precious. It’s up to you if you want to get more of only one good or less from several of them. Every turn you get goods from a territory you must have some population there (supporting your Empire) but in the end they also have to be fed.