How many farms are needed to support a city?

I love ACKS's domain building and campaign building. I've created really interesting areas with it before and find it quite inspiring. But frustratingly I can't ever seem to find out one simple question: To support a city (let's say 3,900 families for a total of 15,600 people) how many farms would be needed to support this city?

It seems like such a basic question that really should be obvious to me, but I might be having a moment because I can't work it out. I want to say a 6 mile hex can support 80 families (in addition to the number of families in that hex). But I don't know where that number came from.

Here's some numbers from me:

Furyondy: 91,250 families (365,000 people)

* Chendl (1 castle): 3,900 families (15,600 people)
* Grabford (1 castle): 3,120 families (12,480 people)
* Crockport (1 castle): 2,496 families (9,984 people)

* Willip (1 castle): 1,875 families (7,500 people)
* Littleberg (1 castle): 1,719 families (6,876 people)
* 25 other towns throughout Furyondy (2 more castles): 13,282 families (53,128 people)

1 hex can support 120 families (480 people) in a city:
* Chendle needs 33 hexes
* Grabford needs 26 hexes
* Crockport needs 21 hexes

There are a total of 64,858 families (259,432 people) working on farms with a total of 338 6 mile farm hexes. This puts the average farm hex at 192 families per hex (with rounding). Given a kingdom size of 1,080 hexes this gives us a kingdom of 31% farmlands

If we adjust to the 300 families per farm hex we get 217 farm hexes. This gives us a kingdom of 20% farmlands.

Anyone want to help me with my numbers? I'm not 100% sure where I got them from (partly Medieval Demographics). Kingdom size is roughly fixed (I haven't gone to the effort of painstakingly counting the exact number of hexes. Feel free to round up to 1,150 hexes) as is total population size. So I anticipate based on these numbers a kingdom filled with ruins with plenty of places for outlaws and monsters to lurk.

Thaks jedavis. I'll just keep going with the numbers I've got then :)

You’re in the realm of the plausible within ACKS’ assumptions I think. On page 231, there’s a table mapping Realm Population to Urban Population, which seems to indicate that most of the time it takes nine farming families to support one urban family (but that ratio can be as low as 4 farming families per urban family in extremely technologically advanced realms). Likewise, page 230 has a table of population density, which caps out at “Medieval France” with 650 families per 6-mile hex. 650 families per hex implies that such a hex could support (roughly) 72 urban families at a normal tech level for ACKS. The upper limit on population per hex is 780 families (per page 129), which would support right about 87 urban families, yeah.

So a city of 3900 families needs about 35000 farming families to support it, which at a Medieval France level of population density is something like 54 six-mile hexes. Granted, that would be a very centralized realm, with just that one city and few or no other towns - ACKS default assumptions seem to be that about 20% of the urban population lives in the largest settlement in the realm, so depending on your centralization preferences you might quintuple that to 260 six-mile hexes, total agrarian population 175000 families, total urban population ~19500 families, and largest city population 3900 families. How many actual farms there are then depends on how many people there are per farmstead, which might be anywhere from 1 to 3 5-person ACKS “families” (or more for something like plantation agriculture…).

You might find this site useful:

Damn too late to the party and the economics stuff already got answered.


Damn too late to the party and the economics stuff already got answered.


Sounds like someone's  monstrous creation is starting to have a life of it's own.