I found an old book of interest when rummaging last eve... A fond, old memory.... Mailbox System circa 2013 http://uorforum.com/threads/mailbox-system.2976/ Happy Birthday UOR!!!
Looking at this map and thinking back to the postal service there was one thing that I never understood, the postal zones in the first place. If anyone were to redo it you'd want to take into account likely population density as a function of real player occupancy. What I mean by this is that you would create the zones by a weighted number of houses (a fortress for example might count as 12 or more units even though its equivalent area of small houses is somewhere around 6) This is purely conjecture and may not necessarily be true but the larger houses are more likely to have active players who consider that their primary residence compared to a small house. Would make the zones a bit closer to real zip code distributions. But that's just me being a nerd
