I see a lot of people placing their cities Civ 2 style. They want to use all 20 squares surrounding the city, including the one the city is placed on. I see many great games play this way, but those are exceptions. What is important now is that corruption will eat away at the power of those super cities as they are farther away. And this perfect placement of cities creates another problem. Time is an issue here.
Although a city's maximum potential is all 21 tiles, they will not reach this peak until the modern era. First, they can only use 7 of the 21 tiles (1 is the city itself) before an aquaduct is constructed. That is all of the ancient era. In the middle ages, it can only use 13 of the tiles, or 2/3 of its potential. After a hospital is made, pollution becomes rampant and the city grows very slowly after this point. Finally, it gets its true potential in the modern era. Great.
Come on, any smart Civ 3 player will figure out the "super city" placement died with Civ 2. Here are the benefits and disadvantages of making smaller, but more efficient cities.
#1- Less corruption. Because your cities are packed closer together, they don't have to deal with as much corruption. This really makes a difference in this game!
#2- Growth. 2 cities grow faster than 1. Having a large number of cities early on will create fast growth, and a power advantage, by the middle ages. This is an obvious, and the best benefit.
#3- Culture! Don't forget that making less cities means less culture. Having a lot more cities means more culture.
#4- Happiness. Luxuries are more useful in my city planning. It is so difficult to satisfy 8 size 20 cities. You are much better off with 14 size 12 cities instead. The population is almost the same, but they are easier to keep happy.
#5- Defence. A sprawling mass of size 20 cities all over the map is very, very, very hard to defend. The cities are much better defended because they aren't all over the place.
#1- Defence!? Yep, big cities get the precious metropolis defence bonus. The value of garrison units like spearmen is lower because they don't get the huge city defence bonus. However, the smaller cities are defended better by offence units because they are closer together. And offence units can fight back and punish whoever wants to mess with you.
#2- Wonder building. The only serious disadvantage to making small cities is that you don't have 1 or 2 super production cities. However, you don't need most of the wonders! They aren't that good! And the best ones are snatched by a great leader anyway, so don't worry about not having 80 production in a single city!
#3- Resources. Yes, making your cities very close to each other will limit your resources. That doesn't hurt as bad because you won't need as many resources, but strategic resources can be harder to obtain. However, this can be prevented by having a reliable ally or conquering early.
#4- Score. The widespread empire will have a higher score because of the territory bonus. So what. It will have more unhappy people, but that part of Civ 3 is underrated in the score section. I bet a small country can beat a widespread one because more cities can grow faster and have an industrial age advantage. You can win if you kill the giant before hospitals are made.
How to use city placement
Normally, 2 size 20 cities ues 42 tiles, or 2 separate city radii. 3 size 13 cities use 42 tiles too. This is very ideal, but you see what I am trying to tell you. You can make 3 size 13 cities with the metropolis defence bonus, and still have the same amount of production and trade as 2 size 20 cities. However, 3 size 13 cities grow 50% faster than the 2 size 20 cities!!!
I am CONSTANTLY scorned and ignored by people that do not like my strategy. I thought that people would have learned by now, but the many succession games I have viewed has taught me otherwise. The main complaint is that you will not get enough territory quickly enough. Land is more important than growth in the score. So, here is how you compensate. Make 3 or 4 core cities first, while your warriors/scouts scout. Then, place your next cities near the AI border. This won't work in MP because they would be attacked, but the computer doesn't really have a clue
Then, fill in your land accordingly! Because you will have very fast growth by placing cities closer, you will be much bigger later in the game. And you can safely assume you will be expanding so much early on you won't hit the size 6 limit. After making aquaducts, you will have a lot of size 12 cities, although very close to each other. Territory is taken early by closing borders, then you make your cities where you want them. It is much, much better than placing cities so they all hit max potential.