What would be a good way of making a 1km wide hexagonal world tile?

I am working on making a game based on hexagonal grids and each grid is 1 km from 1 side to the other. How would I go about creating terrain for these in terms of land formations and such.

I am comfortable in doing this in UE4 on a basic plane but how do I do this for a custom model inside 3DS Max to be ported over to UE4. Just wondering if anyone has any ideas?

1 Hexagonal tile is at the most 1km across with a border along the edge like metal girders found inside most large structures. That is my idea and I just need a bit of support and pointing in the right direction. Never done anything on this scale before haha!