I’m a sucker for urban games. One of the elements I am really enjoying about the 3.0 game I’m in right now is that the entire game is basically urban – dealing with thieves’ guilds, the assassination of the king, building a temple to a new god and all the politics that go along with that (the urban basis for the game is in part because the DM of this particular game doesn’t have a Dungeon Master’s Guide or a Monster Manual or any modules – he’s built the game from scratch using just the 3.0 PHB).

Of course, developing a functional and believable city as the backdrop for such a game is a fair chunk of work. And the believability can be a bit weak if you don’t have much experience in urban planning and organic social growth. The actual map of the city is a nice finishing touch, but is really just there as a prop because it is unlikely that you will ever be in an environment where it matters what street goes where – all that matters is knowing what each part of town is like and where the important places are.

Since I’m in the process of remapping my B/X campaign setting, I figured I’d take the time to detail one of the many smaller cities on the Hill Islands (which occupy the same geosocial place in the campaign as the Purple Towns in the classic Elric saga, if you are familiar with it).

Instead of creating the city from scratch by myself, I figured I’d pull down City Works – a d20 supplement written by Mike Mearls and published by Fantasy Flight Games. The book is broken up into 5 major sections – Characters, City Basics, City Construction, City Adventures and City Encounters. The City Construction chapter (chapter 3) is where we are going today – a full chapter on how to design a city built around a set of random tables. But a lot of this book is good for just about any game, not just this chapter. Chapter 2 (City Basics) is almost entirely system-neutral and provides a good foundation on city politics and systems, Chapters 4 & 5 are packed with tables for random names, interior floor plans, nature of business and peronality traits of NPCs to flesh out a city as well as a whole bunch of material on urban events (fire, plague, siege) and how to set up an urban campaign. Definitely a pretty decent book for someone looking at running an urban campaign.

The first step in mapping out a city is to note the existing natural geographical features that exist in and around the city. Then we need to determine the city size, which in turn will determine the number of “city blocks” that we’ll need to place during the mapping stage.

Since there are so many cities in fairly close proximity to each other on the Hill Islands, most are either very large towns (3,000 to 5,000 persons) or small cities (5,000 to 12,000 persons). Since I’m detailing one of the mid-range cities for my first time using the city building function of this book, I’ll go with 8,000 people (mid-range of the Small City category in the 3.5 DMG). The system used in the book creates a series of city “blocks”, each 500 feet on a side, that you set out in a grid, with one block per 100 residents. So this city will use 80 blocks total (so I have to make sure that there is at least a 9×9 area appropriate for the city when I draw out the terrain).

And now it’s time to draw the terrain – unlike most of my maps, I’ll be using tracing paper set over graph paper, and use the scale of 250 feet per square on the graph paper (so a “block” in the City Works system will be a 1/2 inch by 1/2 inch square). This will be a detail map of the terrain at a natural bay on one of the Hill Islands.

So here’s the map at the end of stage 1 – just the terrain and a rough idea of how big the city will be. Tomorrow I start rolling on the tables to determine how the city is set up.