Terrains[]
As you progress through the technologies, new jobs will become unlocked, allowing you to assign idle citizens to produce new units of value.
Once you unlock the map (Exploration), you will see squares of terrain. Non-desert terrain each have multiple improvements that can be built once the appropriate technology has been researched, which will improve the base production of your city population working in that role.
Note that improvements apply to all cities that are in an adjoining tile - both yours and those belonging to the AI.
Also note that improvements (as of 1.3.6) don't have an owner - so if you build something on a square shared with an AI city, the AI will most likely to sooner or later build something else over your improvement. (AI loves farms and mines, so science camps are not in great danger but merchant posts are).
Terrain Types[]
| Type | Hills? | Improvements Available |
|---|---|---|
| Plains | Yes | Mine, Trade Post |
| No | Farm, Trade Post | |
| Desert | No | Farm(Australia only) |
| Forest | No | Forest Camp, Trade Post |
| Grassland | Yes | Mine, Trade Post |
| No | Farm, Trade Post |
Roads[]
Connecting your cities with a road to your capital increases the gold production. Connecting your city with a city, with which it has a trade route, increases the value of that trade route.
If you are at war with a civilization, which has a city on the road between your capital and another city, that city is not connected to the capital and you need to build a road around that enemy city.
Engineers and industrial improvements[]
Railroads, industrial parks and mechanized farms are only available after +50 points on the Time Travel orientation. They are built by engineers. For several reasons you should accumulate a lot of workers, before they are replaced by engineers or have at least on city auto-producing them. They are much cheaper and faster produced.