I want my cities to transform with major technologies like they did during the agricultural and industrial revolutions. There's really no interdependence of cities in Civ, no metropolises, no rural farming bread-baskets. This also means that cities can't specialize in the game. Even if youre on track with tech, you really cant get a nuclear weapon before 1960 because even if you get Fission in 1930, you still have a wonder (20 turns, even in a very productive city) and an expensive unit to build (another 15ish turns). I propose two simple enhancements that allow cities to become more specialized: A. With the development of Fertilizer (or some early industrial tech, like "advanced machines"), a civilization gets the ability to have one citizen work two farm tiles, freeing up citizens to become specialists or focus on production tiles call this the agricultural revolution. (Citizens left unemployed would automatically migrate to cities where there is a tile or specialist slot for them to work, assuming there is enough food). B. With the development of refrigeration, food becomes a civilization-wide commodity, rather than a city-wide commodity. This will allow cities specialized in production to grow very large, and productive, allowing them to produce late-game units/buildings faster without making them cheaper call this urbanization. (This allows even more concentration in bigger cities, as they are less food limited). (I realize there is a thread already here about the second prong, but since I think there might be some discussion on the part A, I kept this post separate) Big cities might also make good targets too . . .