The movement-cost tool-tip you get from hovering over the Tile-info picture says that the "Road Construction AP Cost" for "Low Mountains Forests" is 200 AP. How this relates to the formula in the Manual...I am not certain. But it does agree with the road construction cost.
Good find (image below)! I think it fits the formula perfectly. 200 (road construction AP) * 20 IP/ 10 AP = 400 IP ... exactly the number I get. It's a steep cost, but okay - perhaps the manual is just out of date.
However... one question begets another [;)]
The rail logistics AP is listed as NA. If I try to build a rail into the low forested mountain, it wants to charge 1740 IP and 1740 iron. So, for the case of rails, the hover-popup seems wrong.
Nevertheless, it looks like the monster costs are intentional and not a bug. It surely is quite an effort to create infrastructure through nasty terrain so it may make sense.
-Mark R.
