Four point one miles on the map, on every map, measured with a wheel. My watch says four point six, and the extra always appears between the same two trees, and it takes eleven minutes I do not remember.
I have walked the same loop in the same forest most mornings for eleven years. It is the thing that keeps me upright.
The loop is four point one miles. I know that from the Ordnance Survey, from the forestry's own path map on the board at the car park, from Google, and from the fact that in 2016 I borrowed a surveyor's measuring wheel from a man at work and walked the whole thing pushing it, which took me two hours and which I did because I had already started to wonder.
Four point one, plus or minus what a wheel does over roots.
My watch says four point six.
I need to explain what a GPS watch actually does, because people think it is a magic distance number and it is not.
It fixes its position from satellites, roughly once a second, and it stores that as a track: a list of points with a time on each. The distance is the sum of the straight lines between consecutive points. That is all it is. It is arithmetic on a list of places.
Which means that to make it say four point six, the watch has to have BEEN in enough places to add up to four point six. There is no setting that inflates it. If it were drifting badly you would see it in the track, as a shape that wanders off the path and comes back, and the path would look like a drunk drew it.
I have exported nine hundred and some tracks. They are all beautiful. They sit on the path.
The extra is not spread out.
That took me two years to establish because I had assumed it was, the way an error usually is.
It is not. If you take my track and split it by the mile, the first mile is a mile. The last mile is a mile. Between the third and fourth mile there is a section, about four hundred metres on the map, where my watch records nine hundred metres.
It is the same section every time.
It starts at a big beech with a split trunk that everybody uses as a landmark, and it ends where the path meets the fire road at a bend. In between it is straight, level, and open. You can see one end from the other. It is four hundred metres and you can see all of it.
The time is the part that has stopped me telling anybody.
Distance is arithmetic and you can argue about arithmetic. Time is on a clock.
That section takes me about four and a half minutes at my pace, and it always has, and I have timed it deliberately hundreds of times.
The watch says eleven.
I have watched the clock at the beech and I have watched it at the fire road, and the first reading and the second reading are about eleven minutes apart, and I have not stopped, and I have not stood still, and the walking I remember doing is four and a half minutes long.
I have tried it with my phone in my pocket recording audio, which I did for a month in 2019, and the audio is eleven minutes of footsteps at my ordinary pace, unbroken, with the same birds, and me breathing.
Eleven minutes of me walking that I do not have.
Other people.
My brother has walked it with me perhaps thirty times. He has a watch too and his does the same thing on the same section, to within a few metres, and when I finally asked him about it in 2018 he looked at his wrist and said, huh, and that was the whole of his reaction, and he has never mentioned it since.
I once walked it with a woman from the walking group who did not have a watch. At the fire road I asked her, casually, how long she thought that last straight bit had taken.
She said, about ten minutes? And then, straight away, no, that's daft, it's nothing, four minutes.
And she stood there for a moment looking back down it.
Here is everything sensible, and I have done all of it.
Different watch. Three of them now, two brands. Same.
Watch on the other wrist, watch in a pocket, watch in my hand held out in front of me. Same.
Phone GPS instead. Same, and the phone and the watch agree with each other about both numbers.
Walking it the other way round. Same section, same extra, so it is not something about how I approach it.
Walking it at night, in the rain, in snow, in August at six in the morning. Same.
Not walking it. I have driven the fire road to the far end and walked that section on its own, out and back, without doing the loop. Out: nine hundred metres, eleven minutes. Back: four hundred metres, four minutes.
That is the only asymmetry I have ever found and I have repeated it eleven times and it holds. It only happens going one way, which I had never noticed in eleven years because the loop only goes one way.
I am not going to build a theory. I do not have one and the ones I have tried on do not fit.
What I have instead is a habit, and I am aware of what it says about me.
I count.
From the beech, out loud, under my breath, one number a step, the way you do. And at the fire road I stop counting.
My count is always about four and a half minutes' worth of steps. Between three hundred and eighty and four hundred and ten, every time, which is right for four hundred metres.
So the watch has me in nine hundred metres of places. The audio has eleven minutes of my footsteps in it. And my own count, which is the only measurement made by the thing that is actually there, says four hundred.
Whatever is being added is not being added to me.
The last thing.
In the March I got to the fire road and my count was six hundred and twelve.
I stood there for a long time. Then I walked back down to the beech, counting, and it was three hundred and ninety one, which is right.
I have been back every morning since and it has been normal every single time.
But I have started stopping at the beech before I go in, which I never used to do, and having a look down it, which you can, because it is four hundred metres and straight and level and you can see the whole thing.
And I have got into the way of thinking that if I ever look down there and cannot see the fire road, I will not walk it.