I don't know if this was reported before, but BI has an additional fix for historical battles.
Now it is possible to place rivers (with water) near to the cities, as found by CeltiberoKarmipoka.
Here you can see the differences in the battle editor (the text is in Spanish, but the images are clear enough): http://www.celtiberos.net/modules.ph...&p=34955#34955
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