Fogbreaker
There are only three shapes a walk can have. You can go out and come back the same way, you can go round in a loop, or you can go one way and get home by some other means.
Almost everybody picks the first one, almost always. It is worth knowing exactly what that costs, because the number is clean and larger than it feels.
The arithmetic
Walking reveals a corridor roughly 30 metres wide, fifteen metres to each side.
An out-and-back of 6 km is 3 km of ground walked twice. A loop of 6 km is 6 km of ground walked once. Same distance, same time, same effort.
| Shape | Distance walked | Distinct ground | Ground revealed |
|---|---|---|---|
| Out-and-back | 6 km | 3 km | 0.09 km² |
| Lollipop (1.5 km stem, 3 km loop) | 6 km | 4.5 km | 0.135 km² |
| Loop | 6 km | 6 km | 0.18 km² |
Exactly double, top to bottom. Not approximately: an out-and-back walks every metre twice by definition, so it covers half. There is no version of this where the out-and-back catches up.
Why people choose it anyway, and they are not being stupid
This is where most advice of this kind goes wrong, so let me say the obvious thing first: the out-and-back is chosen for good reasons.
It has an abort option at every point. At any moment you know exactly how far from home you are, and turning round is always available. A loop commits you. At the far side of a 6 km loop you are 3 km from home no matter which way you go, and if the weather turns or a knee complains, that is a fact you cannot negotiate with.
It cannot get you lost. The way back is the way you came, already seen, in reverse. A loop requires either knowing the area or trusting a route you have not walked.
It works everywhere. Loops need a connected network. A trail up a valley, a pier, a spit of land, a dead-end lane: some places only have out-and-backs, and that is geography, not laziness.
Those are real. The mistake is not choosing the out-and-back, it is choosing it by default when the loop was available.
The lollipop is the answer most of the time
Look at the middle row of the table again, because it is the useful one.
A lollipop is a stem out, a loop at the far end, and the same stem home. It keeps most of what people actually want from an out-and-back: the first and last stretch are familiar, you are on known ground when you are tired, and the navigation risk is confined to the middle section where you are freshest.
And it recovers half the lost area. In the example above it is 0.135 against 0.09, which is a 50% gain for changing nothing except the far end of a walk you were doing anyway.
Make the stem shorter and the loop bigger and it converges on the full loop. That one dial is the entire technique.
Four ways to use it
- Convert your regular one. Take the walk you already do as an out-and-back and find a return that is one street over. On most street networks this costs nothing in distance and immediately doubles the ground.
- Loop out, stem back. If the reason you go out-and-back is the abort option, invert it: do the unfamiliar loop in the first half while you are fresh, and keep the known stretch for the end.
- Use one-way transport. Bus or train out, walk home. The route is then a pure one-way line with no repeated metre at all, and the commitment problem disappears because the bail-out is a bus stop rather than a retreat.
- Keep the out-and-back where it belongs. Bad weather, low light, unfamiliar area, tired, alone, or a genuine dead-end route. The shape exists because it is safe. Use it when safety is the thing you want.
Where the shapes become visible
None of this is visible from inside a walk. A repeated route feels productive while you are on it, because it is: you are still walking, the distance is real and the exercise is real. What it stops producing is ground.
A fog map shows the distinction immediately, because it only credits new ground. The map starts covered and walking clears the fog in a strip around you, which means an out-and-back clears a strip on the way out and then nothing at all on the way home. Fog of war, but for real life explains how the mechanic works, and Territories turns it into a percentage per neighbourhood.
The first week of using one is where most people discover they have been walking the same 3 km for years.
The honest limits
A tight loop double-counts too. If your loop is a lap of one small block, the 30 metre corridors on opposite sides overlap in the middle and the doubling shrinks. The rule holds for loops wide enough that the two sides do not see each other, which in practice means anything bigger than a couple of blocks across.
The way back is not identical to the way out. Reversing a route genuinely does show you a different view, different light and things you had behind you. That is a real argument and it is worth something. It is not worth 50% of your ground, but it is not nothing.
And the fog clears outdoors, on GPS. Fogbreaker is free on iOS and Android. If you want the version of this argument that applies specifically to gridded streets, in a grid every zigzag is exactly the same length, which is what makes the parallel return free in the first place.
