Choose a cache site on dry ground away from water, trails and the base of large trees, and fix its position by measured distances and bearings from two or three lasting features, held in memory by a few trusted people and not on a page a stranger could read. A cache you cannot find is a cache you do not have, and a written record that leads a finder to it defeats the purpose, so the real work is balancing the two.
Part of Hidden Food Caches
Cache location selection is the choice of a hiding site and the method of recording it so that the right people can find it again and nobody else can.
The Site Must Be Findable By You And Nobody Else
The parent article’s selection rules are: away from water, since not in flood zones nor where the water table rises seasonally; away from trails, since walking past a cache often creates a path others may follow; near landmarks, since you must find it under stress, at night, possibly injured, using unmistakable ones such as large rocks, distinctive trees and stream junctions; and, if the container is metal, buried near other metal such as old fencing to mask its signature.
Emergency Caches gives several more: dry soil that drains (test a 600 mm hole in the rainy season; if water seeps in within 24 hours, choose another site), no frost heave, at least 3 m from large trees, stable terrain, and away from high-traffic areas. It also says the opposite on landmarks: do not cache beside the big distinctive boulder or lone oak, which attract attention and make the site memorable to others, and use three fixed, non-obvious reference points instead.
Both are right about different things. Use distinctive features to navigate to the area, and place the cache at a measured offset from them, not against them. The feature that gets you there is a landmark; the cache sits somewhere nothing marks.
What You Need
- Two or three lasting reference points — boulders, rock outcrops, stream junctions, a surviving wall; not trees that may fall or fences that may be moved
- A compass, with its declination noted, or a method of taking bearings
- A measured pace, found by walking a known distance
- A short, trusted circle — whoever must know
Method: Offset, Triangulate, Remember
Step 1: Choose the ground by the rules above. Mark nothing at the site.
Step 2: Pick two or three reference points that will last as long as the cache. Trees die, streams move, buildings are demolished and fences are shifted; a rock outcrop usually stays.
Step 3: Measure the position from each. Take a compass bearing and count paces from each point to the cache. Three points give a cross-check; two give a fix.
Step 4: Calibrate your pace. Walk a known distance, count paces, and divide.
Step 5: Record it in the way that suits your risk. The parent article says to use distance and bearing from landmarks, to record the information in a coded or memorised system, and that a written record can be found while a memorised one cannot. Emergency Caches says to keep a register in a waterproof case in the primary store, to have it memorised by two trusted people, and not to keep the whole register in one place. These differ in what they risk: memory risks loss when the holder dies or forgets; paper risks capture. A middle way is to teach the location to two people in person, walking the route, and keep any paper part incomplete, a key without which the page is meaningless, held away from the dwelling.
Step 6: Re-walk it. Walk to the cache from each reference point in daylight, and again at night, and correct your numbers.
Worked Example: What A Small Bearing Error Costs
Suppose the cache is 100 m from one reference point. You hold the bearing within plus or minus 3° and your pace count within plus or minus 5%. These error sizes are assumptions for the example, not measurements.
- Sideways error from the bearing: 100 m × tan 3° = 100 × 0.0524 = 5.2 m either side, so a band 2 × 5.2 = 10.4 m wide.
- Error along the line from the pace count: 5% of 100 m = 5 m either side, so a band 2 × 5 = 10 m long.
- Area to search from this one fix: 10.4 × 10 = 104 m². Probing every 0.5 m, each probe covers 0.5 × 0.5 = 0.25 m², so 104 ÷ 0.25 = 416 probes.
Now replace the pace count with a second bearing from a point about 60 m away at roughly a right angle, held to the same plus or minus 3°.
- Sideways error from the second bearing: 60 m × 0.0524 = 3.1 m either side, a band 2 × 3.1 = 6.2 m wide.
- Area where the two bands cross: 10.4 × 6.2 = 64.5 m², so 64.5 ÷ 0.25 = 258 probes.
A second crossing bearing cuts the area from 104 m² to 64.5 m², a reduction of 1 − 64.5 ÷ 104 = 38%, and a third reference point shrinks it further. The model treats the errors as independent and the ground as open and level, so treat the numbers as a way to compare methods, not as a prediction.
Common Mistakes
- Choosing a tree as the only reference. It can burn, fall or be cut.
- Placing the cache against the landmark. It tells anyone who sees the landmark where to look.
- Writing the location in full on a page you carry. A person who finds the page finds the food.
- Telling one person only. If that person dies, the cache is lost.
- Never testing the numbers. An untested bearing is a guess.
Safety
Remote sites and unknown ground
Going alone to a remote site invites injury with nobody to help; tell someone when you go and when you will be back, without saying where if that is the secret. Do not choose a site in flood plains, on unstable slopes, beside cliffs or on thin ice, and do not dig where the ground has a history of dumps, burials or buried services. Carry water, and do not search in the dark with a probe near a drop.
What’s Next
- Learn next: Inventory and Rotation — keeping the record true over time
- Combine with: Retrieval Under Pressure — using the numbers when it counts