I have to stop you here. As you can see in my quote in the first post:
All icons have to use "forest clearing.bif" (to be indestructible) so they all looks exactly the same. The difference is seen only when you right-click on one of those icons and info pic appears. If you choose to make 4 indestructible cities in one province you will see 4 the same icons in the review panel. I hope it won't ruin the whole thing for you.all landmarks share the same icon and description but Info Pic can be different
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