This is a simple tool for generating locations in a campaign collaboratively, whether at the start or partway through. It's intended for both wargaming and roleplaying campaigns and it relates to the recent discussion with bombasticus at this post.

It's been tested with a group of five players who barely know each other and went down very well.

The central idea is this: the forces or characters that the players are guiding are part of the wider landscape, so they reflect this landscape and have relationships with elements of it. This tool treats them as a kind of inverse function to find the known nature of a given location.
                                                                                                                              

You'll need all of the players, plenty of dice (I'll assume d6s), a sheet of paper and at least one pencil or pen. The key elements are size, links, centre and features, and generation involves rolling dice on the sheet and marking the positions to form a map.

Size

The group agrees the type of location to be created and how big an example it will be, on a scale of 1 to 6, e.g. for settlements, a village might have a size of 1, a hive city 6.

They also agree a rough scale for use in marking the map, e.g. 1:1,200, or 1" = 100'.

Links

Each player gets 1d6 links per force or character and per point of location size, e.g. if the players are creating a large town (size 3), they might get 3d6 links each. However, if one of the players is guiding two forces, that player would get 6d6 in total (1d6 x 3 x 2).

Each link is represented by one roll of a d6. A link is strong if the result is equal to or less than the size, e.g. a link to a large town (size 3) is strong on a result of 1, 2 or 3.

As each roll is made, the number of links remaining for that player is reduced by one.

Centre

The group agrees the key feature of the location, e.g. a lake or high pass, and draws this at the centre of the sheet of paper, or passing through the centre. If the specifics are hard to agree, and there's no GM willing to determine them, use Talysman's blob or line.

Features

The group agrees a list of other features that the location might have, e.g. for a large town wells, walls, gates, markets, temples, offices, stores, power stations, sewer outlets etc. These are arranged in order of appearance and marked as either punctal or linear.

Generation 

The group works down the list. For each feature, a player may use any number of links available in an attempt to ensure that this feature is present. A player gains one free link for each force or character that the group agrees is especially relevant to the feature.

All of the players rolling for a given punctal feature roll all of the dice simultaneously onto the sheet of paper. If a link is strong (i.e. the result is equal or less than size) the position of the die is marked and one example of this feature is at that point. If it's off the sheet, an arrow is drawn at the nearest edge pointing towards it, the distance marked.

For example, in a group of four players generating a large town (size 3, scale 1:1,200), two decide to roll for scrapyards. One decides to expend one link, the other two links. The latter player guides an engineer and the group agree this is a further potential link, increasing the number of dice rolled to three. The two players roll all four dice at once. Three finish on the sheet, one 2" off it. The results are 1, 3, 3 and 5, so the 5 is discarded. The two finishing on the sheet each have their position taken by a scrapyard. At the edge nearest the third scrapyard an arrow is drawn and marked "Scrapyard, 200'".

The result on the die can be used to represent the significance of the feature or be taken as the perimeter of the feature in inches or any other measure, as agreed by the group.

A linear feature is found as if punctal, with the group agreeing the lines or gentle loops connecting them immediately after rolling, or the players taking turns to mark one each.

Points along lines are found by moving the die to the closest point on the closest line.

The group then expend remaining links to add contours, major routes and districts, as well as name elements and suggest relationships. Each link is worth 1d6 countour lines, major routes, district boundaries, names or relationships. Players take turns, one roll per turn, but each can invite any or all to contribute to any large project out of sequence.
                                                                                                                              

I'd suggest approaching all of this with an open-minded attitude and trusting the group to make sense of the results as they come in. That said, if the site has to perform a certain function or have a fully laid out street plan with names and it's clearly not going to as the links run out, a little tweaking could be agreed, maybe as extra links across the board.

It's worth noting that the map produced needn't be the final form, or show the totality of the location. It's more a reflection of the knowledge of the forces or characters. It may be there are various minor examples of each feature present, or other features altogether, to be added as needed, encountered or found, or as they would naturally appear over time.

I'm sure this can be improved and adapted to work better for given gaming groups, and I'd be interested in thoughts on that as well as any feedback on how it goes if you use it.
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