View Full Version : Population vs. Map Size

02-27-2012, 09:02 PM
I'm still in the process of finishing the regional map for my campaign, but thinking ahead a bit I'm wondering how BIG some of the cities should be. There are beautiful maps on here and a lot of discussion about mapping technique, but I haven't seen anything about population and city size with the exception of this post (http://www.cartographersguild.com/showthread.php?8305-Cartographical-Economics-and-Demographics-A-Guide-to-Realism) by terminal.

Assuming the 180 people/sq.mi. mentioned in there... That would mean that a 10,000 person city (which is really big by D&D standards) would span apx. an 8 mile diameter area. What does an 8 sq. mile city look like?

I'm posting a few examples from the Cartographer's Choice section as examples, not as my work... hope this is okay.
The City of Castran (http://www.cartographersguild.com/showthread.php?14630-Featured-Map-The-City-of-Castran-by-Zong) - How many people would this city house? It's freakin enormous so... is this a 10,000 person city?

Haibianr (http://www.cartographersguild.com/showthread.php?7539-Haibianr-by-mearrin69) - This one's a little smaller. Maybe 2,000?

Trying to get a feel for how large of a map I will need for a few of the locations my players will be exploring. I hope you're able to understand what I'm trying to figure out. Thanks for any input!

02-28-2012, 04:30 AM

Hard question to answer as every city is different and depends on its building history context, geographical and topographical environment and so on.

I would suggest you to take time and read eXeditious Retreat Press great "Magical Medieval Society: Western Europe" book. It presents a way to determine area of your city according to the population size and for each you got the "buildings density", thus you can see how your 'houses' are spread around the place. When you got the number of area and their size, it is far more easy to draw it using graphical tools (Photoshop, Illustrator and others that enables you to check for area size/surface (acre, are, square feet/meters...)). Then you would have the representation of your city.
Aside of this, I would suggest a simple but effective website (you can download the script freely to store it without being "connected") which allow you to compute (according to historical and empirical material) the size of a city, size of surroundings, size of cultures fields and even population 'classes' and business... http://www.welshpiper.com/medieval-demographics-online/

I base all my works on those tools.

Hope that helps!


02-28-2012, 08:14 AM
At a scale where the typical building is as large as the fingernail on your pinkie (roughly 1"=100') the 8 mile city would fit on a map roughly 35 feet x 35 feet. This is about the scale that the detailed 'villages' are drawn at.

At 4 buildings per pinkie nail (roughly 1"=200') the 8 mile city would fit on a map roughly 18 feet x 18 feet. This is about the scale that modern city atlases (like for utility design) are drawn at.

At 100 buildings per pinkie nail (roughly 1"=1000') the buildings are dots and the roads are lines and the 8 mile city would fit on a map roughly 3.5 feet x 3.5 feet. This is about the scale that modern city road maps are drawn at.

These are just very rough figures to give some idea of scale. As a practical matter, cities and towns are comprised of neighborhoods of about 500 people each, so one could have a 1"=2000' map (2' x 2') of the whole city and a 1"=200' map of the neighborhood where most of the action takes place.

02-28-2012, 12:07 PM
That's a great tool Anoril, thank you. Helpful info from both of you, but I guess I phrased my question poorly. I meant more what does a graphical map of a 10,000 person medieval fantasy city look like?

To use one of my favorite maps on here so far by Aval Penworth, what would the population of this city (http://www.cartographersguild.com/attachment.php?attachmentid=24473&d=1273062868) be? (hope it's ok to link someone else's work as an example.

02-28-2012, 04:57 PM
I've thought about this a couple of times as well. I try to count the houses and depending on how many floors they have multiply with 5 x floor to get a rough number.

Try looking here as well : http://www.rpglibrary.org/utils/meddemog/

02-28-2012, 05:24 PM
You will have to look for it (I think in reference material) but a while back I posted a link to an article which had population statistics of cities around the world in medieval times and explanations as to population sizes.

02-28-2012, 09:56 PM
Merged and moved out of the WIP forums to the general question forum.

-Rob A>

02-29-2012, 10:42 PM
Figured anything related to towns/cities should go in there. Now I know better ;)
Cleaned up my double postings due to the merge.

My bad; thanks RobA.

03-04-2012, 03:15 PM
A lot depends on what kind of architecture you have and how prosperous people are. Also, how practical artificial lighting is. Most of us have a lot of stuff compared to any but the wealthiest of historical personages, and we spend much more time active indoors thanks to electrification and all of its spin-off effects. Thus we have an increased need for residential space. OTOH, our great cities can build very high, so can be much more compact even given our need for larger spaces.

Typical medieval town/city building is probably the two-story with business on the ground floor and residence above. Rome had apartment buildings up to four stories high. If magic lets your people build higher (or if they can dig underlevels and make them habitable), they can squeeze in even more people.

Basically, first you need to figure out how the people live. That's going to determine how concentrated or spread out the population is.

03-04-2012, 04:06 PM
Well ... actually, a lot of medieval buildings were 3 and 4 story affairs if they were larger. The city limits were usually set by decree with different laws applying inside and outside, so as the population grew it often built up. Also, city walls are hard to maintain effectively if they're too long, so again - focus on density.

The actual population density of medieval cities was often ridiculously high, with thousands of people jammed together in what to us seem surprisingly small areas.

The city you've linked I would say, at a quick guess, you easily have 5,000 to 10,000 people living there.

04-21-2012, 10:14 PM
Assuming the 180 people/sq.mi. mentioned in there... That would mean that a 10,000 person city (which is really big by D&D standards) would span apx. an 8 mile diameter area. What does an 8 sq. mile city look like?

Careful! You've made a mistake! In the link you gave, terminal gives 180/sq mile as the upper limit for a COUNTRY. That is, the average of all the area in the entire kingdom. In the fields it will be much lower and in a city, much higher.

I've seen figures in various places online saying that in medieval cities, population densities were as high as 30,000/sq mile. A couple things to keep in mind if that seems impossible. First, when people ran out of room, they built up, often adding floors above the ground that were bigger, hanging out over the street. Second, families were larger back then to keep up with infant mortality you might have six or seven people living in one or two rooms. Here is a useful site that I stumbled across just today: http://www222.pair.com/sjohn/blueroom/demog.htm It's an article that explains a lot of the math behind those calculators people are linking. (I know that it is the source of the the math for the defunct calculator terminal linked in his .pdf)

Edit: And, scrolling down the page, it looks like it is the source for the math in the Welsh Piper calculator someone linked a couple posts ago too!