General Information
The terrain spaces surrounding your City are called valleys. Each has a terrain type and a level associated with it(see below). When hovering over a valley with the mouse pointer, you will see information about the benefit you will receive when you have conquered it. Clicking it will give information about current ownership and also give the possibility to scout it out or attack it. Scouting or attacking a valley (without a city!) does not break the Beginner's Protection, even if it is currently owned by another player. (Age 2 servers do not allow you to scout nor attack while under Beginner's Protection.)
 Valley types
Each valley has one of the following terrain types: Flat, Grasslands, Swamp, Lake, Hill, Desert or Forest. All of these terrain types, except for Flat, provide a percentage production increase to your city's resource production when you have conquered them. The Flat is different in that it does not provide a production bonus, but it is needed as a building location for a new city. Although The Flat terrain does not support a increase in production, you are able to colonize it and build a new city!
 Valley production bonus
The following table gives an overview of terrain types, their levels and the associated resource production bonus:
If you watch a valley over time, you will see that its level goes up slowly until it reaches 10. Then it changes back to level 1. Keep track of this if you want valleys of a particular level because if you wait long enough, you will have the level you want, though you may have to wait some days or weeks.