Time or distance?

[Umbran]

I'm sorry... there are unresolvable problems with this system.

Hardly. Remember, in the beginning, maps were not created with accurate satellite imagry. They were made based upon estimated distances, and the estimation was commonly based upon travel time, and people managed even with the inaccuracies.

Or, if you prefer, you must remember that even the common flat maps we use today have unresolveable problems, because the map is flat but the ground is round. Somehow, despite that, people get by. No large-scale map is perfect.

In the example you give, all you really need to do is pick a convention. In this case, the most likely thing people want ot get from the map are the paths and travel times between cities. They are not typically interested in the interior of swamps. So, you base how far apart on the map the towns are based upon typical travel time. If, typically people travel through the swamp, then the swamp size grows to show the travel time. If typically people go around the swamp, and the trip is quicker, then the map will depict the distance/time taken to go around more accurately, and the swamp itself becoems a lesser feature.

 

[Piratecat]

I love this idea. It's different from what I normally do, but it's a really interesting way to present an adventure.

 

[VoiceOfReason?]

It would be a relatively simple and only moderately time-consuming proccess to mark the roads with travel times, so their actual length on the map can be ignored.
The same could be done with canals and other waterways that are used for travel. If your world has an ocean that is exploited for traveling purposes, your coastline will need to be longer than the ocean it borders, or have trade routes marked in a similar fasion.

A good point was made in that maps (more primitive ones to a larger extent) are all innacurate to an extent. The only reason a map concept like this seems alien and/or impossible to us is because we haven't seen anything like it work. If I recall correctly, several tribes of north american natives including the Aztec tribe of mexico used time-related mapping systems as opposed to distance-though most were not a traditional 'map'.

 

[TerraDave]

A map in three parts?

Instead, a useful thing would be to make a "triptych" from your authoritative map,

And it has three panels and can be folded together...

This is good for player hand outs, especially with some of the flavour suggestions in the thread. But the authoritative map will still be the main ref, to deal with alternative means of transit like mounts, wagons, boats, magic, or something like weather--a cold snap can have different impacts on travel in different types of terrain--if you want to get fancy.

 

[Asmor]

One thing you might do is draw by distance, but put the grid on by travel time. That way the 'squares' on the mountains are smaller, the 'squares' on the roads are long and thin, etc.

I really, really like this idea. I probably wouldn't implement it as a grid per-say, but rather start out by overlaying long strips following the countours of the roads, then work outwards from them, filling in a day's worth of travel per section.