WalkSOS / Being seen
A quarter of call-outs are somebody nobody can find.
Figures: Mountain Rescue England and Wales 2024 incident statistics, reported by Ordnance Survey and the BMC. MREW publishes its own annual reviews at mountain.rescue.org.uk.
What the call-outs are actually for
The first three are shares of all 2024 call-outs. The last is the time of day they came in, which is the descent, and the hours before dark.
The ones in red are the same problem. Somebody is there. Nobody can see them.
Why a person on a hillside disappears
It is not resolution. At 500 metres a walker subtends about three arcminutes, and the unaided eye resolves about one, so a person at that range is comfortably large enough to see. The problem is that three arcminutes of olive and grey sit inside a hillside made of olive and grey, alongside several hundred rocks of roughly the same size and tone.
Flat cloud makes it worse by removing shadow, which is what normally separates an object from the ground behind it. That is the weather a great many searches happen in.
The arithmetic of a banner
Angular size is size divided by distance. A 1.85 m banner at 500 m is about 13 arcminutes across; a 0.5 m-wide walker is about 3. That is a factor of nearly four in width, and the banner presents 1.11 square metres of a single flat tone rather than a broken, mottled outline.
The colour does the rest. White is the furthest thing from a wet hillside in flat light, so white is what gets spotted. The SOS is red because once a crew has seen the white, the letters say what it is rather than leaving them to wonder about a bit of fly-tipped plastic.
See the geometry move on the home page
Where the busiest teams are
Of all 2024 call-outs in England and Wales, Llanberis took 9% and Ogwen Valley 5%, both in Eryri. Wasdale, Keswick, Langdale/Ambleside and Edale took about 4% each — three of those four are in the Lake District, which is why the routes page leans where it does.
The demographic shifted too. In 2024, 18-to-24-year-olds were the age group most often needing help, ahead of any other.
Five well-walked routes, with altitude profiles and a note on what makes each one hard to be found on.
What to dial, what to say, how to send your position, and the two-minute thing to do before you leave the house.
A note on what this page is not. WalkSOS is a new product and has no rescue stories of its own. Nothing here is a customer account, because there are none to tell. Every figure above is somebody else's published statistic and is linked to its source.