Maps are probably my biggest weakness when it comes to GMing. I know I've said I'm weak on NPCs and social interactions before, but my maps are truly hideous. In fact, compared to the maps and layouts that my fellow GMs make, even just the ones I know locally, my maps are like a two year old that got into the PB&J before walking on blank paper. That said, mapping is often considered a fundamental skill and I figure to work on it I need practice. Fortunately, while I suck at mapping I do know some of what goes into it. Today I want to talk about making a city conceptually. Then, later - maybe - we'll talk about drawing that map.
Believe it or not, the terrain a city is built on matters. Cities don't just spring up without reason, and the terrain around them often helps to shape that reason. Furthermore, no one is going to build a city on a giant sand pit and you're not likely to get a massive city atop the spire of a mountain (though, in a fantasy universe, carved into a mountain is a different story.)
So before you know your city you need to know your terrain. Does a river split through the build site? Does it have coast access? Mountains? Forests? Plains? What is the area like around it? After you know that...
Original Purpose Of Settlement
How did the city start at its very beginning? Boston and New York were ports for ships to land after coming to the new world. Detroit was a fur trade and military fort. Every city has a very humble origins. For fantasy universes this often means a fort was built for defense. However, trade, mining, travel, and magical ley lines also make very good reasons for a settlement to start.
Once the initial settling happens more people will be drawn, especially if the place is successful. More people will draw even more people - as long as the area can handle it - and then you'll have yourself a city.
For example, many cities in a fantasy setting are the settlement that grew around a fort. So the military fort came first, and was probably built atop a hill. Then some people moved "close" for protection. Others came in. Eventually there was a full town built around the fort. That draws trade. The trade brings more people. Eventually you have a city and maybe the fort has become a castle. Point is, you have the city.
Start From The Beginning
So, from here, we are at the beginning where we can map. We need the terrain set out first. Then we place the original purpose (for simplicity's sake start with a wizard tower or a fort.) Then think what came next. Where would those people build? What would they build? Then who would come next?
For example, say we have a fort first. The fort houses the men and all that fun stuff. However, they'll need horses stabled so maybe a stable comes next. They need food too, so maybe some farmers are encouraged to build near. The horses need shoes, the fort needs weapons, and the farmer needs tools so a smithy could come next. Now you have a full settlement, and the place is probably known. Might be time for some enterprising soul to make an Inn. Now travelers can come. Travelers mean coin and a need for supplies. The general store gets set up. Now the general store needs to stock and re-stock which means merchant traffic. That can mean more inns. It can also mean more of everything else. But by now we've got the beginning.
This, the mapping in order, is usually where I end up failing pretty bad. I just place things, trying to do the finished product from the get go, instead of going slow and thinking things through. Maybe tonight I'll take a crack at going slow and see what happens.