map design dilemma

[valmont]

I want to design a historical scenario that involves England, Scotland, Spain, France, the Benelux countries, and Rome. I want the map to accomodate all these countries, but that means large areas of unoccupied land. How do I keep the AI from expanding into the unused portions of the map? The only thing I can think of is to fill it in with forests which the AI won't build on. Is this an acceptable solution?

[Michael Daumen]

Are you planning to use fighters or units that can attack air units? If not, you can place units as impassable terrain.

[techumseh]

In another recent thread, it was reported that the AI will only build new cities on terrain which is in the original position of grassland or plains in the Rules Text. If so, then if you changed glacier (for example) to give it the look and values of grassland, the AI would still not build cities on it.