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, and other obstructions), but I’ve found it useful to have some reference points and rules of thumb.
HORIZON: The horizon is 3 miles away at sea level.
NEIGHBORING HEXES: Passing through the center of a hex, neighboring hexes cannot be seen. If the path is biased, the nearest hexes can usually be discerned (depending on terrain).
MOUNTAINS: Mountains can be seen from 6 hexes (75 miles away).
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) |
| 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 |
This material is covered by the Open Game License.
The horizon distance chart is particularly useful to me – thanks!!
When your players spot tall objects in the distance, do you have a means for them to know how tall/far away it is, or do you just give them a description along the lines of “You see a range of mountains to the north”?
Also, how would you handle a character climbing a particularly tall tree in a forest to see the surrounding terrain? Would the character’s height only count how far they are above the forest canopy (Since in this case, that is effectively the “ground” that is preventing them from seeing too far)?
Thank you very much for posting this series of articles. (Actually, thanks for pretty much every article you write)
This comes in a particularly timely manner. Was just thinking about this topic and what reasonable encounter distances might be in different environments.
I know this post more terrain related, but on a tangential topic: any thoughts on dungeon encounter distances? Just pure line of sight?
Re: Tall objects in the distance. Largely dependent on circumstance. In general, I favor vague approximations of distance unless special effort is taken to determine actual distance. (This applies to dungeon exploration, too.)
Re: Climbing trees. In terms of horizon, yes. Assuming that the forest is continuous, I believe its correct to consider the canopy to be “ground level” in terms of determining how far you see. For objects taller than the canopy, however, getting above it may help you see them at farther distances.
Re: Dungeon encounter distances. Generally just pure line of sight. Theoretically, I try to take sound into account, too. But I’m not always as consistent with that as I’d like to be. Although a properly prepped monster roster helps a lot in adjudicating that sort of thing.
Your encounter distances for desert/plains (and sometimes mountains) seem short. I do a lot of trekking in remote places and it isn’t uncommon to see other trekkers from a mile away, especially if they are wearing colorful clothing, or are moving against a stationary and mostly uniform background.
Ken
Those numbers are pulled from 3.0. I’d tend to agree that, methodologically speaking, they’re not perfect.
The formula for the distance to the horizon, assuming no interposing obstacles/terrain is: 1.23 x the square root of the altitude in feet, on Earth.
For 6 feet this is 3.01 miles.
Subtract a couple inches for the top of the forehead to the location of the eyes, rounding to 3 miles is a good approximation. Or assume added height of shoes/boots.
One of my great granduncles studied to be an engineer and our dad had one of his books with this formula and a chart. My brother and I went nuts figuring out how far one can see from the top of a tower, or the maximum height one could levitate or fly.