GURPS Navigation (Land) and Terrain

[M036462]

I'm designing a post-apocalyptic hexcrawl and have been reading up on all the various rules for travel and navigation, like After The End2, DF16: Wilderness Adventures as well as The Alexandrian's excellent commentary on d20 hexcrawls. One of the things I've noted is that GURPS Navigation rules seem to consciously omit penalties for terrain type, which strikes me as odd. My only personal experience with navigation is the (under)sea type so I wanted to get everyone's opinions here on the topic.

I would think that areas where it is difficult to find a follow a landmark would be more difficult to navigate in then others, so areas like dense forests and jungles should get a penalty, as well as areas like moorland where it is relatively featureless and the undulating terrain makes it more difficult to keep the landmark in view.

Part of the problem comes from what the consequences of a failed navigation check. ATE and DF16 treat navigation checks as giving a bonus or penalty to travel speed. Terrain type is already factored into travel speed and some of the modifier is undoubtedly due to navigation difficulty of the terrain, which leads to not adding an additional penalty to the check. I am planning on using a failed navigation check to send the party into the wrong hex which makes me lean toward including a terrain penalty for navigation.

So, should terrain have a penalty and if so, what magnitude for what terrain, or should navigation not be linked to the terrain type?

[Fred Brackin]

Originally Posted by M036462

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So, should terrain have a penalty and if so, what magnitude for what terrain, or should navigation not be linked to the terrain type?

The use of Task Difficulty Modifiers is usually assumed for all Skills. What they should be is not a simple question. all I can say is pick your absolute worst terrain and make it a -10 (if you think it really is almost impossible) and then graduate your way up from that to less difficult environments in an orderly fashion.

Real World experience in traversing featureless wilderness without technological aids is probably in short supply around here. I know I have none. It's never played a big part in games where I GM'ed either. Players who have psyched themselves up to have their characters slay a dragon will just be annoyed by getting lost on their way to his lair.

What i'd do is make sure that some PC has a reasonable level of competence in the task and assume that in poorer terrain he works harder and takes longer.

[safisher]

GURPS Low-Tech provides a fairly comprehensive discussion of Navigation, including navigating by landmarks, and celestial navigation.

[M036462]

The rules in GURPS Low-Tech seem to be limited to Navigation (Sea). As a former naval officer that is something I actually know a good deal about and can attest that the rules there are good, but sadly, don't seem applicable to my current conundrum.

[whswhs]

Originally Posted by M036462

The rules in GURPS Low-Tech seem to be limited to Navigation (Sea). As a former naval officer that is something I actually know a good deal about and can attest that the rules there are good, but sadly, don't seem applicable to my current conundrum.

I think they could be adapted to land navigation, but it would be necessary to think carefully about which parts still apply and which don't.

[M036462]

I think what I'll do is use the terrain modifiers from Mass Combat to determine navigation penalty because they approximate what I'm going for. If plains has a penalty of 0 then I'll set the penalty equal to terrain modifier-8. Thus the penalties are:

Arctic -2
Desert -1
Hills -2
Island/Beach -2
Jungle -5
Mountain -4
Plains 0
Swampland -4
Woodlands -3
Dense Woodlands -4

[Say, it isn't that bad!]

People have gotten lost in a few square miles of woodland. You might want to double those penalties.

...Granted, that's modern people; but medieval peasants mostly lived in the middle of farmland, surrounded by farmland, and the next village over was past a few trees; featuring yet more farmland.

The medieval fantasy depiction of dense forests surrounding isolated villages was not actually typical, or so I've heard from people who I hope are more knowledgeable on the subject. ;)

[Tinman]

Don't forget that navigation assumes you have proper tools.
Even in woods if you have a compass, map & even a few landmarks, it shouldn't bee too hard to keep on course.
I've done it in hills, desert & light woods terrain.

[Tinman]

Originally Posted by M036462

I think what I'll do is use the terrain modifiers from Mass Combat to determine navigation penalty because they approximate what I'm going for. If plains has a penalty of 0 then I'll set the penalty equal to terrain modifier-8. Thus the penalties are:

Arctic -2
Desert -1
Hills -2
Island/Beach -2
Jungle -5
Mountain -4
Plains 0
Swampland -4
Woodlands -3
Dense Woodlands -4

Hills & mountains make great landmarks. I totally see where trees & blocked vision make things hard also featureless terrain like arctic or plains.
I don't think those modifiers work for the navigation.
I do think they are spot on for movement.

[Say, it isn't that bad!]

Originally Posted by Tinman

Don't forget that navigation assumes you have proper tools.
Even in woods if you have a compass, map & even a few landmarks, it shouldn't bee too hard to keep on course.
I've done it in hills, desert & light woods terrain.

While true, I've heard of experienced hikers getting lost in said few miles of woods.

Although - I'm not a hiker, but there's probably a difference between "experienced trail hiker", and "experienced wilderness hiker".