The ancient city-states in Greece were all located on places were there was a Mediterranean climate, meaning long dry summers, pleasant spring and autumn, and wet mild winters. This was a perfect place for farming wine trees and olive trees, and the Greeks did so, both, for their own usage, and for trade. From the grapes they were making wine, and from the olives they were making olive oil, both of which were highly demanded and well paid products, and the Greeks used them for increasing their wealth.
