It was only meant to be a short run, starting late in the evening from a campsite in Kent I was sharing with a dozen friends. I quickly find a path along the river and follow it west for a few fast kilometers. I'm dressed for speed, carrying nothing but my phone.
Eventually I hit an impressive bridge and pause to admire the river from mid-span. Now, I hate out-and-back runs. My rule is, wherever possible, make a loop. Google maps on my phone makes it look like there's probably a path back along the other side. I decide to give it a go, promising myself I'll turn back in a few hundred metres if it doesn't look good. I still have nearly an hour of daylight left.
The track meanders, occasionally becoming overgrown by blackberry. It's slowing me down a bit, but still heading vaguely in the right direction. The track gets worse and worse and I decide to bail - there's a road only a couple of hundred metres ahead, probably running back to the bridge. I push through, leaping thorns, slowing down to pick my way through bad patches.
A hundred metres short of the road, the track dead-ends in a wall of bramble. Rather than backtrack, I try to force a shortcut through the field the track has been circling. There's tall grass on the near edge, but it should flatten out in the middle.
It doesn't. I get off-course in the tall grass, but manage to get back to the river. There's no direct way to get to the bank, but it joins a narrow patch of forest. It's near sunset now, and I'm not pleased to see my phone's compass pointing me in. Right. I'll have to push through the forest a couple of hundred metres to the riverbank, where I'll pick up the running track. This isn't great, but it's doable.
At this point things start to get a little worrying. I succeed in clawing my way through the forest to the river, but there's no path on the north bank. I turn east instead, hoping to reach the confluence where there should be a bridge, but the going is very, very slow. As the light fades, I'm getting very easily turned around, and only my phone's compass is keeping me true. I'm not quite panicking but I'm moving fast, not caring as thorns tear at my exposed thighs. I have 8% battery remaining.
Time to take stock. The sun has set. With nothing to orient on inside the wood, once the phone shuts down, I'm lost. Nobody knows I'm here and there's nobody in shouting distance. I'm in thin shorts and a running top. It's summer, so I won't freeze to death, but I'll potentially have a miserable night and a humiliating morning if my friends call in a search party.
I consider turning back to the west again, and retracing my steps all the way back to camp - but that route runs more than a mile the wrong way through deep grass, and it's getting far too dark to navigate. I need to find clear terrain where the light will last longer and I can move faster. I pull up the satellite overlay on google maps. On the other side of the thinner tributary to my north, the forest is replaced by field.
I'm going to have to cross it. All of the other options are worse.
Tracing the river, I get lucky; there's a fallen tree, and I walk along it to the other bank. But on the far side there are very tall, thin, trees, with gaps only slightly wider than me. The satellite view says it's less than fifty metres. I raise my arms to protect my head and punch through to what I hope is the field.
Only it isn't. It's grass all right, but mixed with blackberry, taller than me. This is the worst of the lot, but I'm committed now, so I push through, taking giant-sized steps and knees-up leaps. Previously, I'd have called this "impassible". Turns out it isn't really.
There's no way I have time to skirt the last creek. So I turn east again and smash through the thorny undergrowth around it. I don't even bother looking for a crossing this time, hoping it's as shallow as it looks. Dripping, I hit clear ground on the other side and hammer home along the running track, back up to speed at last.
When I get back to the campsite, my friends look at me like nothing's happened. Someone asks if I've been for a run.
Later I replay the whole experience on Google Earth. What really happened here was that I got suckered by the sunk cost fallacy, throwing good kilometers after bad as the path deteriorated. What I'd like to say I learned was "when you're buzzed from running, and tired, and under time pressure, watch out for terrain that gets worse and worse until it's too late to turn back". But what I actually learned was this: