Note: For this discussion of the playing techniques I am using Civilization III Complete. This is an all-in-one edition that incorporates the two expansions, Conquests and Play The World. This is readily available from multiple sources.
When you look at how humans settle in new lands, you see that one of the biggest issues is to look at the land and figure out what it is best used for. I used to teach Economic Geography, and this was a determining factor in where people settled. Access to water is necessary to irrigate crops, and you also need good farm land. But you also need access to other resources, such as stone for building, timber, clay for making pots, and so on. And in Civilization III (and indeed all Civilization games) it is just as important. One of the biggest mistakes new players make is to ignore the land or failing to develop it properly. In Civilization III and later versions this means building Worker units and putting them to work building roads, mines, and irrigation. This is good, but you can do a better job with a little research into land types in the game and what cities can handle. For research a good starting point is the built-in documentation, the Civilopedia, which you can consult while within the game. It is generally accurate, but every once in a while the Civilopedia tells you something that just isn’t true. Sometimes this is because the programming changed along the way and no one got around to updating the documentation. If you think you have run across something like this, you can check one of the fan sites like Civ Fanatics or Apolyton. If the documentation got it wrong these sites will most likely have the right info.
Cities and Tiles: The BFC
The first point is that in all Civilization games it is cities that produce things, and it is cities that work the land with the population each city has available. Don’t be fooled by the national borders that arise as your culture grows. Your borders may well include tiles that no city can work because the tiles are not within the area of any city. Cities in Civilization III can work an area that looks like a letter “X” that is somewhat distorted because of the isometric view of the map. The tiles are all squares, as they were in the first two games, and would be again in Civilization IV. It is with Civilization V that they switched to hexagons in place of squares. When you settle a city, that square sits at the center. Then around that square you can place 8 more squares, one at each side and one at each corner. You now have 9 squares in a 3×3 pattern. Then extend each side by one square, adding 3 squares to each side, but not adding anything at the corners. You now have the cross shape, and I will use the terminology of Civ players and call it the Big Fat Cross (BFC), which totals 21 squares. Make sure you learn this, it is key. No city can work a tile that is not in its own BFC. Second, it takes one citizen to work a square. So if you have a city with a population of 3, only a maximum of 3 squares can worked.
Now, you want to develop your squares to increase their productivity. First, every citizen in your city requires 2 food just to stay alive. If you can produce more than 2 food per citizen, the excess will accumulate in your food box until you have enough to add another citizen, and then that citizen will require 2 food, but will be available to work another tile. If however you produce less food than 2 per citizen, the difference will be drawn out of the food box, and when it is empty a citizen dies. So we have a simple Malthusian model going here. Now when you settle a city, if you pick a good spot, you may have one or two tiles that already produce 2 or even 3 food, But in general to increase food production you need to build irrigation, which is done with your worker units, and requires adjacency to fresh water or to another irrigated tile. But to build units like workers you need production (shown as Shields), and that comes from building mines, another action that workers can undertake. You can increase the productivity of your city by building certain buildings, but buildings requires gold to maintain them, and one of the best sources of gold is tiles with roads on them, where the gold represents the trade that can occur with roads. So barring any special resource, you can have three things that a tile can contribute: Food, Production, and Gold. And your worker units can increase the amount each tile contributes by building Irrigation, Mines, and Roads. So this is your starting point. You want to identify the best tiles in the BFC of your city, make sure your citizens are working those tiles, and improve them as necessary to increase their contribution by using your workers.
Tiles Types and Yields
There is a nice and concise summary at StrategyWiki for the terrain tile types. And since they each have a distinct appearance, you can quickly pick them up. But note that you can right-click on any tile and get a pop-up window that will tell you what kind of tile it is and what the yields are. In Civilization III any tile within your city can be made to produce something, often several things, just by putting someone to work on it. And you can increase the yields by developing the tile with one of your Worker units. So, if you have a Hill tile, it will produce one Food and one Shield if a worker is placed on it. But you can develop it by building a mine, and that adds two Shields to the yield. Building a mine is the only thing you can do with Hills, you cannot build irrigation on them. Another possible way to add production is to develop a Mountain tile. They do not produce any Food at all, and cannot be irrigated, but they will produce one Shield if a worker is placed there, and building a Mine also adds two more Shields. So these tiles can be summed up as:
- Hills: 1 Food + 1 Shield undeveloped, 1 Food + 3 Shields with a Mine
- Mountains: 1 Shield undeveloped, 3 Shields with a Mine
So if you had both of these tiles in your BFC of your city, which one would you chose to put to work? Obviously, the Hills tile is better by producing the 1 Food, so that would be the preference.
If you open the city screen by clicking on the city, you can see where your workers are assigned because there will be icons of the yield on the square being worked. If you click on that square while in the city screen, that worker will be removed from work and turned into an entertainer. That is something you want to avoid in most circumstances. You want to keep your workers productively working if at all possible. Three more tiles you will frequently encounter are:
- Plains: 1 Food + 1 Shield undeveloped, +1 Food if irrigated, +1 Shield if mined
- Grasslands: 2 Food = 0/1 Shield undeveloped, +1 Food if irrigated, +1 Shield if mined
- Forest: 1 Food + 2 Shields undeveloped, cannot be developed
The different thing about Grasslands is that some of the tiles are “Bonus” tiles that yield one Shield when undeveloped. You can usually tell because there will be a little white dot in the center of the tile, but as with all tiles you can right click on the tile and read out the yields on the popup to be sure. If you put a Mine on one of the Bonus Grassland tiles you will get and additional Shield, for a total of 2 shields. Or you can Irrigate it to get a total of 3 Food, and if it is a Bonus tile you will get the 1 Shield as well. So those bonus tiles are the best ones you can have, ignoring special resource tiles, because you can get to a total yield of 4, combining Food and Shields, from the one tile. And in the early game that is very important. And it is the early game that will make or break your outcome. You need to carefully guide your civ in the early turns to get on a winning path.
The other tiles you may encounter are:
- Coast: 1 Food, +1 Food with Harbor
- Desert: 0 Food + 1 Shield undeveloped, +1Food irrigated, +1 Shield mined
- Floodplains: 3 Food +0 Shields, +1 Food irrigated, , +1 Shield mined
- Jungle: 1 Food +0 Shields undevelped, cannot be developed
- Ocean: 1 Food +0 Shields, +1 Food with Harbor
- Sea: 1 Food +0 Shields, +1 Food with Harbor
- Tundra: 1 Food +0 Shields undeveloped, +1 Shields mined
Now some explanations can be added here. First, note that Forest and Jungle tiles cannot be developed. However, you can clear those tiles with your worker. Forest when cleared will produce whatever is under the Forest, often Grassland, but sometimes Plains or Tundra, and Jungle will clear into Plains. And there are 3 water tiles. Coast is a water tile adjacent to land, Sea is a shallower water tile, and Ocean is the deep water tile. You can distinguish Sea from Ocean by the color: Sea is lighter blue than Ocean.