I’m curious as to what projection this is mapped on. It seems very… Horizontal.

If the OP is using GIS, it can be even easier.

Your first two steps are spot on, but then step three could simply be to add a large buffer for each capital and use some and/or/nor/xor (I’d have to look up to be certain) rules to have the buffer zones not overlap, but end where touching. Apply a color scheme and you’re in business.

Oh! It totally does. I guess I’ve just never had to apply distances in such a way that they’d butt up against one another to become what looks like basic geometry.

Thanks!

I think I’m too stupid to understand this. How are they straight lines and not at a diameter / in a circle from any given point? It seems… wrong.