A while back I tried to work out a system that lets you track overland travel on a 6-mile hex map without getting any fractions for the number of hexes traveled in a day. I did come up with one that is very simple:
- Characters move with a light load, medium load, or heavy load. (6, 4, or 2 hexes per day)
- Each hex is on average either easy terrain (full speed) or difficult terrain (half speed).
This results in six possible combinations of progress in a day, each one a whole number. (Horses would make no difference because horses only run faster than humans but walk about the same speed, and except for a few special bred and trained horses have worse endurance than humans. Every single fantasy RPG gets this wrong.)
The one thing that bothers me a bit about this system is that the speed for travel with a light load through easy terrain comes out at 6 hexes per day. Which would mean 36 miles. (50km) Such progress is absolutely possible. Some people have managed to do 100 miles in a day, and there are reports of soldiers with their equipment doing over 30 miles in a day without roads. But this would be a very big ask even of most people who walk long distances as regular exercise. And those who can do it wouldn't be able to do it more than two or three days in a row at the most.
However, what kind of people actually travel long distances with a light load? In most RPGs with encumbrance, a light load is actually really light. It's often the limit for thieves silently climbing up castle walls. With just food, weapons, and armor most PCs in many games will end up with a medium load and then you add all the travel gear on top of that. And if just one character moves at medium load speed, then the whole party does. As I see it, overland travel with light load would be very rare, and it really only makes sense for messengers. And messengers in a world where all nonmagical long distance communication is done on foot would be the 0.1% of best long distance runners in their society.
So I think saying that travel with a light load on easy terrain comes out to 36 miles per day might still be "believable enough". Normal travel speed for marching armies or traveling adventurers would be 24 miles per day and by all accounts that really isn't anything unusual for soldiers who do daily marches for hundreds of miles as a regular part of their service.
What do you think about this?
So a few thoughts: This is something I was actually really thinking about. Aside from the PCs being adventurers who slay dragons and gods, and therefore being reasonable candidates for being very fast sprinters or whatever, your players are probably unfamiliar with the reality of traveling on foot. DnD hand waves a lot of traveling stuff, and encourages you to be ready for a fight, which naturally encourages thinking of character sheets in certain terms.
If your players want to travel light, then you don't have to think hard to punish them for not having at least the bare minimum of camping gear. I mean, I'm a seasoned camper, but the last time i went, my family forgot the mallet. After driving in stakes with a frying pan, I promise you I wont forget that ever again. And we weren't even backpacking.
Your thoughts also exude weather; Ryuutama is a game with a traveling subsystem. It's not perfect, but it may have some good ideas for you to consider.
Of course you can always include more detail to get more realism.
But my main goal is to make using hex maps for travel more convenient to use while still maintaining the 6-mile resolution. That means all daily travel distances have to come out as full increments of 6 miles, and the equation to calculate speed has to be easy enough to do by memory without looking up any tables. I don't think it's mathematically possible to produce something like that with more factors going into it.