This is a useful cheat sheet I created for understanding what characters can see in the wilderness. In practice, sight lines will vary quite a bit (due to hills, forest canopies, atmospheric haze, and other obstructions), but I’ve found it’s useful to have some reference points and a few rules of thumb.
HORIZON: The horizon is 3 miles away at sea level.
NEIGHBORING HEXES: Passing through the center of a 12-mile hex, neighboring hexes cannot be seen. If the path is biased, the nearest hexes can usually be discerned (depending on the terrain).
Design Note: This is one of the reasons I prefer a 12-mile hex. Unless the PCs take special action to see farther, you’ll generally be able to focus exclusively on the hex they’re currently traveling through.
MOUNTAINS: Mountains can be seen from 6 hexes (72 miles) away.
Design Note: My research indicates that most mountain ranges have an average height of 3,000 feet. If you do the math, you can see an object 3,000 feet high from about 68 miles away, which I then rounded up to 6 hexes. Or, if you reverse the math, I’m saying that at 72 miles you can see the occasional peak that’s up to 3,500 feet high in that range or thereabouts. A very tall peak of 10,000 feet could theoretically be seen from 10 hexes away on a clear day.
ELEVATION: Distance to the horizon in miles is the square root of (feet above sea level x 1.5 feet). Add the height of tall objects to the viewer’s. Atmospheric haze will eliminate the ability to see even the largest objects more than 3-5 hexes away.
| Height | Horizon |
|---|---|
| Halfling | 2 miles |
| Human | 3 miles |
| 10 ft. | 4 miles |
| 25 ft. | 6 miles |
| 50 ft. | 9 miles |
| 100 ft. | 12 miles (1 hex) |
| 400 ft. | 24 miles (2 hexes) |
| 1000 ft. | 39 miles (3 hexes) |
| 1500 ft. | 48 miles (4 hexes) |
| 2500 ft. | 60 miles (5 hexes) |
SIGHTING
Characters may seek out a good location for seeing long distances by taking the Sighting watch action. Height is obviously a factor here, but finding the right sight lines can be equally important. (Climbing a tree is all well and good, but if it’s at the bottom of a valley the effect will be mitigated.) This is also why simply being “on a mountain” doesn’t automatically translate to great sighting: you’re usually surrounded by other mountains.
As a general rule of thumb, assume that characters can find a location granting them 50 feet of height (or the equivalent thereof). This will allow them to see into neighboring hexes, and possibly even see notable locations within those hexes or their current hex (which may or may not require a Wisdom (Perception) check).
If you call for a skill check to find a sighting location, consider using a fail forward technique: On a success, the PCs get the normal benefits of sighting. On a failure, they might only be able to make out the terrain type of two or three of the nearby hexes (and no details thereof).
If circumstances suggest that the PCs would have great sight lines without needing to take special effort, that’s great. It might still be appropriate to allow them to take the Sighting action to improve their line of sight even more, extending their vision by another hex.
ENCOUNTER DISTANCE
When an encounter is generated, the distance at which the encounter may be detected will depend on the terrain in which it is occurring. (If the encounter is with a group of creatures and both sides are surprised – i.e., they do not detect each other – it’s technically possible they will pass each other without ever realizing it.)
The figures here represent typical circumstances on the ground. If the PCs are keeping watch from the top of a stone tower, for example, it’s quite possible for them to spot potential threats at much greater distances.
| Terrain | Encounter Distance |
|---|---|
| Desert | 6d6 x 20 feet |
| Desert, dunes | 6d6 x 10 feet |
| Forest (sparse) | 3d6 x 10 feet |
| Forest (medium) | 2d8 x 10 feet |
| Forest (dense) | 2d6 x 10 feet |
| Hills (gentle) | 2d6 x 10 feet |
| Hills (rugged) | 2d6 x 10 feet |
| Jungle | 2d6 x 10 feet |
| Moor | 2d8 x 10 feet |
| Mountains | 4d10 x 10 feet |
| Plains | 6d6 x 40 feet |
| Swamp | 6d6 x 10 feet |
| Tundra, frozen | 6d6 x 20 feet |
Coincidentally, I did do the math just a few days ago.
From the peak of a local promontory, it is possible to see the horizon 43 miles away.
1.17 × sqrt(height+elevation in feet) = nautical miles
Yeh, a chart is easier =)
It should be noted that those distances are true technically only for a world with a radius of curvature equal to Earth’s. Most fictional worlds are smaller (if one looks at the travel time between zones of polar and equatorial climate), but it might be better to just gloss over that weirdness.
A small note: elevation in feet above sea level is not what matters; feet above the *surrounding terrain* is what matters. We generally understand this intuitively with respect to heights like “halfling” vs “hill giant”, but when it comes to “how far away can I see that mountain” remember that the height that matters is (height of mountain) *minus* (height of where I’m standing).
Something I would ad is a better WEATHER TABLE, the one in pag 109 is kind of sparse, but I like you only need to roll 3d20. Maybe something that’s separated by seasons or with the sort of magical weather hinted at TCoE could spice things up.
I have a bunch of questions about encounter distances, because circumstances can have an enormous effect. Maybe Part 5 on Encounters will get into it, though?
Do you have guidelines for encounter distances if one or both parties are surprised? Size of the caravan? Moving fast or slow? Night or day? With or without light sources? With or without outriders?
Also, sometimes encounters start when you *hear* something rather than see it. (Knowing something is out there but not being able to see it is awesome. Seeing a collection of hungry eyes shining dimly in the reflected light of your campfire is also awesome.) (Okay, it’s awesome for the DM.)
I generally just make something up for all of these, with the general story goal of having an encounter on different terms than the last one we played. But always curious how other people do it. I guess you could roll the 3d6x10′ and use the result to decide if the parties stumbled into each other or heard each other coming a long way off.
This is useful information that provides some nice basic guidelines. Thanks!
Nice spotting spot from the Troll tongue, that.
Climbing that high is no joke either. Climbed to about 2500′ just recently, and
1: it takes hours and hours even on farm tracks, mountains are annoyingly steep and uneven.
2: there is nothing up there, almost nothing grows, and the weather is both sudden and brutal.
3: even with a perfect line of sight, looking 40 miles into the distance is like looking at the moon in the daylight, there’s a whole blue sky and then some between you and what you’re looking at.
Camera images of distant things these days use filters that human eyes just don’t have.
With haze you can’t even see big mountains at 12 miles. Clear sky you’ll only see the highest contrast stuff at 60 miles, like snowcaps against a clear sky, and even then it helps if the sun’s at the right angle.
Plus, you can’t see over stuff that’s too close to you. Which makes climbing extra annoying with all the false tops you meet on the way up. Over the crest and what do you see? Another crest, right there, and without tracks, aiming for the highest one is basically impossible on short notice.
@croald: The encounter spot distance tables are a guideline/tool for determining the distance at which detection is possible. You’re right that circumstances will cause this to vary, but keep in mind that you don’t have every square inch of the wilderness mapped with sight-line accurate precision.
I don’t really “know” anything about where the random encounter is happening. I’ll use the random die roll here to inform/prompt my improvisation of those details. For example, if they’re traveling through the forest and I roll an encounter distance of 20 feet, what does that tell me about the area of the forest where the encounter happens? Probably something different than if I’d rolled 120 feet, right?
In 3rd Edition you could actually use the guidelines for Spot checks to determine the precise distance at which each group saw the other (if ever). 5th Edition Wisdom (Perception) checks don’t have that, but the same basic principles apply: If surprise is indicated by the initial checks, the actions of the party which has surprise will determine when/how the other group becomes aware of them (if at all).
Things like travel speed are systemically baked into this by, for example, giving characters disadvantage on their Wisdom (Perception) checks when moving at fast speed or through conditions of poor visibility.
I’m making notes for my Numenera hexcrawl and I copied these tables into, but I extended the horizon table a bit due to the possibility of Numenera schenanigans putting the PCs really high up.
1 mile: 88 miles
2 miles: 125 miles
5 miles: 215 miles
For reference, 5 miles about how tall the Clock of Kala in Numenera is. The Clock is stated to be 30,000ft. tall, which puts it at just under 1,000ft. taller than Mount Everest (29,032ft.)
Hi Justin. Out of interest, where did you get these encounter distances from? I notice that they are slightly different to the ones in the 5e DM Screen.
They’re derived from the 3.0 SRD. The 5E values are not open source.
Happened to succeed on my check to spot a few errors in the wilderness encounter distance table. 🙂 If they’re meant to come straight from the D&D 3.5e DMG that is.
Moor and Swamp are flipped – in the DMG, moors are 6d6 x 10 and swamps 2d8 x 10. This makes sense with moors typically being more open and swamps being more forested.
Both hills have the same value here, but in the book, gentle hill is instead 2d10 x 10.