a) surrounding natural limit (e.g. mountains, deserts, sea shore, sometime large rivers)
b) available movement facilities (e.g. road, bridge, navigable river)
c) natural resources (mainly food, but stones and woods also, until good transport let move them from far
d) cost of estate and buildings (not sure of words, I mean that citizen try to balance between cost of building higher palace inside existing city wall -because of need for protection, too- and cost of terrain outside -so pushing city limit a bit far-.

That given, cities grow, not necessary in exact circle shape

I think that Cyclotron7 suggestion is good: city infrastructure can affect city size as pop. number.

I played with other suggestions (by stuff2 and others) on the Satellite cities thread , developing a tentative model.

I think it can be mentioned here too, because is related to way to manage cities growth.

All started by suggestion of "village" or "suburb" concept. I liked the concept, but I'm more inclined to model them borrowing feature from SMAC Supply Unit (the Crawler).

A normal (i.e. CIV II style) city can build not only "Settler" units - at the expense of 1 population point - but also "Village" units (looking for a better name ) at no population cost.

As in SMAC you can move your Village unit outside city radius and then "Plant" it where you want to use a terrain resource.

The village can't grow, can't be managed as a city;

1) The village unit only use the square where it's "planted", as Supply unit do, and the resources are automatically routed to original city (Support city). I'm pondering if it can only exploit a resource at a time (chosing from mineral, trade or food, as in SMAC), or it can exploit all available resource, but consuming one point each for self maintenance.
E.g. working on a square that give 2 food, 2 trade, 1 mineral, the Original city will gain 1 food and 1 trade (village use 1 food, 1 trade, 1 mineral for self support). Someone should balance this.

2) Once built, the Village unit can be moved no far than 2 movement point from Original city - if you have a connecting road or a river it count as 4 square - railroad count 6 square). With this limit we avoid that village become unrealistical far from original city (SMAC weak point, IMHO).

This is very easy to apply: let the unit have two movement points, apply movement rules and automate its "found village here" at the end, as fighter crash "out of fuel" in Civ 2

With variable city radius mode 2 implemented, we can have a good simulation of early village exploiting precious resource 2 square far from original town, then included in city radius as city grow.

Included village can be left where is (as happens in SMAC with supply, you negate city workers use of that square) or disbanded (Original city gain half production as usual) as if villager "join the city" but without change on Population number.

Using this "village" you visually simulate suburbs and related village, without introducing revolution on Civ2/SMAC already tested design solutions.

I let open another possibility, that may be is too much micromgmt hassle: migration.

A village can be moved ("ghost town" ) on a new place, negating village production for that turn (as in civ artillery fire rules):

- if resources become consumed (random event - no penalty for migration)
- simply because you change your mind about use of that square, e.g. letting them free for your city (forced migration, may be a minor atrocity under not tyrannic government)

I bet it can be nice on visual side, too: think about lot of small icons of villages, placed on best resources squares, visually using the space now left empty between cities.

My opinion about the "villager" unit: The "villager" unit can be the settler, but when inside a radius of 2 from the main city (or maybe 2 x road/railroad multiplier x terrain multiplier) you will have (beside the usual b-build command) a v-village command.

Also, when the city grows and expand, including now the village inside the city's border, the village can't join the city without a certain discovery or city improvement (for example mass-transit). IMO disbanding/relocating the village should be harder or less profitable than joining it to the city.

Oh, one more question: when the city has a radius of 2, but can't gather a behind-the-mountain/river resource, can you send a villager there?

This could be included into the PW system. You should also be able to upgrade a village to a city at a certain cost.

quote: My opinion about the "villager" unit: The "villager" unit can be the settler, but when inside a radius of 2 from the main city (or maybe 2 x road/railroad multiplier x terrain multiplier) you will have (beside the usual b-build command) a v-village command.

I started with the same double use of settler, but a settler cost 1 point of population, so you have more return for your building cost if you use it to (B)uild a new city. No one will use it to build a village instead!
OTOH, if (V)illage is only a kind of work command as (R)oad, i.e. doesn't cost the whole unit in the process, IMO the Village improvement become too much
unbalancing (too much return for the original unit cost).

quote: Oh, one more question: when the city has a radius of 2, but can't gather a behind-the-mountain/river resource, can you send a villager there?

Simply apply movement rules: if a road/bridge/tunnel/mountain pass put the square on admitted radius, then it's ok, otherwise not.

BTW, thank you for your support.
I really hope that some of our ideas, here at Apolyton forum, will ring the right bells to Firaxis, but it's really nice to share ideas here just for the enjoyment of the process

Choice__________________________________________________ Votes
1.expanding, more than 3 circles radius______________________ 5
2.expanding, max. 3 circles radius___________________________ 9
3.expanding, max. 2 circles radius___________________________ 6
4.fixed style city radius, with 2 circles_______________________ 4
5.I don't know/I don't care__________________________________ 1

A lot of people like the idea of expanding city radius. The size of the city radius is, however, subject of debate. Some people think that 2 circles are enough, others want unlimited, huge cities. I think the most reasonable solution, combining several proposals, is the following:

1. In the early stages of the game, cities start at a size of 1 "circle" radius. Later, when the efficiency of your civ is better, cities could start at a size of 2 or even 3 circles radius.

2. Limiting a city to a size of 3 circles sounds like a good compromise, but the limitation should be not a fixed one, but dictated by efficiency (gathering from a distant tile should be less efficient than from a closer tile). So, if somebody wants a city with 5 circles radius, fine, make it possible, but not worthwhile (at least in terms of resource gathering efficiency; huge cities could have other advantages). Of course, tile efficiency could increase over the time, discovering the proper techs.

3. Cities should grow not in exact "circles", but following some natural borders: mountains, sea, large rivers, desert. Of course, these natural borders will limit the city's growth only until the proper tech is discovered (for ex. bridge building for rivers) or the proper TI or CI is built (road, railroad, harbor, offshore platform).

4. A good method to gather resources from a distant tile (especially when the city has only a 1 size radius) is the "village". (see Adm.Naismith's earlier description ). When a city grows big enough to exploit itself that tile, the village becomes a suburb and joins the city. However, villages could join the city only if the city has a proper "mass transit" or other city improvement.

To be fair (and having mine fingers in both, I hope I am ) idea about available square limited by natural obstacle AND village concept can be too much if mixed.

I suppose for pratical reasons (design, programming and playability) Firaxis should chose one of the two.
Of course I hope they can mix nicely, but I think is better to criticize myself in advance, just in case...

I'm just a Civ fan dropping in some ideas (hopefully good ones ). The decision and the implementation is Firaxis' job

21 over 4 is over 5:1 (nice attack advantage, still the defensive party must add a +200% for "conservative Firaxis design" )

Ok, expanding radius seem the most wanted; difference between radius must depend from play test, for balancing and playability reason. I can trust on alfa and beta testers for this tweaking.

CTP2 already introduced it (with some unbalancing trouble, it seems), so Firaxis can look and improve from others trial.

Easy task this time, you Firaxis team

As cities get bigger some sort of village/suburb structures do need to appear around the city. This can reduce productivity.... Admiral Naismith's idea sounds pretty good.

Two big cities should be able to merge , if York and Manchester is near each other it should be new city: "York-Manchester"

or one big city should split into two or three cities if there is to many minorities in the city. If London have 49% english, 40 % russian and 11% german population London should be two cities: "English-London" and "Russian-London".

(These ideas are mayby alittle bit too crazy)

Choice___________________________________________________ Votes

1.expanding, more than 3 circles radius______________________ 8
2.expanding, max. 3 circles radius___________________________ 10
3.expanding, max. 2 circles radius___________________________ 6
4.fixed style city radius, with 2 circles_______________________ 4
5.I don't know/I don't care__________________________________ 1