Highland Trail 550: the obligatory kit, and where it goes on the bike
The organiser of this event publishes a mandatory kit list and a self-support ruleset. The widely-read route guides for it carry neither. The list is eight items long, it is quoted below in full, and the rules around it are what make shelter something you carry every night rather than something you decide about each evening.
Rule 7, in the organiser’s own words
Rule 7 — the obligatory kit
DECLAREDEight items, from the body that runs the event, carried by every rider on every night.
“Sleeping bag, tent or bivvy bag, waterproof jacket, waterproof trousers or waterproof shorts, an insulation layer, shoes that you can comfortably walk in for several hours, front and rear lights, helmet.”
No mass, volume, temperature rating, brand or specification appears anywhere in rule 7. Item 5 is "an insulation layer" with no rating; item 1 is "sleeping bag" with no comfort limit. Any figure attached to these is somebody’s to justify, and it is not the organiser’s.
Highland Trail 550 organiser · source · read
- 1Sleeping bagUnconditional. No comfort limit given.
- 2Tent or bivvy bagThe rider’s choice of two.
- 3Waterproof jacketUnconditional.
- 4Waterproof trousers or waterproof shortsThe rider’s choice of two.
- 5An insulation layerUnconditional. No weight or type stated.
- 6Shoes that you can comfortably walk in for several hoursA use test, not a specification.
- 7Front and rear lightsBoth, not either.
- 8HelmetUnconditional.
Why it is not optional, and it is not the weather
Three rules close the book-a-bed escape hatch, and they close it from three different directions. None of them alone would be enough.
Rule 3
DECLAREDPrivate lodging is out even when it is arranged on the night — a friend’s spare room is not a commercial service available to all challengers.
“Only use commercial services that are available to all challengers. No private resupply, no private lodging.”
Highland Trail 550 organiser · source · read
Rule 5
DECLAREDYou cannot leave the kit somewhere along the route and collect it.
“No gear or food caches.”
Highland Trail 550 organiser · source · read
Rule 6
DECLAREDThe organiser names the exact escape hatch as its example.
“No prearranged support before you begin your ride, e.g. booking a B&B, arranging to meet a vehicle.”
Highland Trail 550 organiser · source · read
What the rules do not say, which matters as much. They do not ban walking into a hotel or bunkhouse you happen to reach and paying for it like anyone else — that is a commercial service available to all challengers. What they ban is pre-arranging it, using private lodging, and caching. Rule 7 then requires the sleeping bag and the tent-or-bivvy to be on the bike either way, which is why shelter is non-optional on a route where you cannot know in advance where nightfall lands you.
Where the shelter goes — and on one frame, nowhere
A sleeping bag and a tent or bivvy are the two bulkiest things a rider carries, and neither has a packed volume anywhere in this product — no mass, no pack size, no brand, by construction. So this is not a subtraction. It is the question that comes before one: which positions for bulk each frame has at all. Three reference frames, and every verdict is the fit engine’s. The bag envelopes it reads are the only MEASURED thing on this page.
Small · 47 cm
- Seat pack
- No seat pack in our catalogue mounts on this frame at all. Refused: Ortlieb Seat-Pack 11 L at 11.0 L, needs 160 mm of exposed post, yours is 120 mm; Apidura Expedition Saddle Pack 14 L at 14.0 L, needs 150 mm of exposed post, yours is 120 mm; Tailfin AeroPack at 18.0 L, needs thru-axle mounts, your frame has none.
- Handlebar
- Largest clean fit is 9.0 L — Restrap Bar Bag 9 L, 22 mm to the cables at full lock. Reported Tight and so not counted: Ortlieb Handlebar-Pack 15 L at 15.0 L, 2 mm to the headlight bracket — inside the margin a photograph-measured frame carries, and a product claiming a centimetre cannot spend a boundary case as though it were room.
Medium · The Mule
- Seat pack
- Largest clean fit is 11.0 L — Ortlieb Seat-Pack 11 L, 180 mm exposed post is 20 mm more than it needs. Refused: Tailfin AeroPack at 18.0 L, needs thru-axle mounts, your frame has none.
- Handlebar
- Largest clean fit is 9.0 L — Restrap Bar Bag 9 L, 22 mm to the cables at full lock. Reported Tight and so not counted: Ortlieb Handlebar-Pack 15 L at 15.0 L, 2 mm to the headlight bracket — inside the margin a photograph-measured frame carries, and a product claiming a centimetre cannot spend a boundary case as though it were room.
Large · 58 cm, three-pack fork
- Seat pack
- Largest clean fit is 18.0 L — Tailfin AeroPack, nothing on this frame limits it.
- Handlebar
- Largest clean fit is 9.0 L — Restrap Bar Bag 9 L, 22 mm to the cables at full lock. Reported Tight and so not counted: Ortlieb Handlebar-Pack 15 L at 15.0 L, 2 mm to the headlight bracket — inside the margin a photograph-measured frame carries, and a product claiming a centimetre cannot spend a boundary case as though it were room.
One frame of the three cannot mount a seat pack of any size, and there are 3 separate reasons rather than one — two exposed-seatpost lengths and an absent mount standard. On that frame the shelter rule 7 obliges you to carry has to go on the bars or in the triangle, and the largest bar bag the engine calls a clean fit is 9.0 L. That is not a recommendation. It is the constraint a rider on a small frame is planning inside, and no page that does not know the frame can raise it.
Rain on one day in two, at named stations
| Station | Days of rain ≥1 mm | Rainfall | Mean daily min | Days of air frost |
|---|---|---|---|---|
| KinlocheweWest coast, Torridon — on the route · station | 15.09 days | 117.65 mm | 5.95 °C | 1.70 days |
| Tulloch BridgeSouthern and inland, the Loch Laggan to Rannoch side · station | 14.53 days | 95.33 mm | 4.64 °C | 3.59 days |
| Altnaharra No 2Far north, the Sutherland end of the loop · station | 13.92 days | 71.66 mm | 4.15 °C | 5.27 days |
May, because the organiser’s window is late spring and the group start is late May. Three official stations, chosen because each sits against a different part of the loop rather than because the numbers were convenient. They are not averaged together: they measure different places, and their mean describes nowhere. None of the three station pages publishes its own altitude, which matters — a valley station understates what an 800 m pass does.
Met Office, 1991–2020 long-term averages · source · read
All three stations record measurable rain in May: 13.92 days of it at the driest of them and 15.09 days at the wettest, so the spread is barely a day. That is a stronger claim than the totals, which vary enormously — Kinlochewe gets 64% more rain than Altnaharra No 2 but not on meaningfully more days. So the frequencygeneralises around the whole loop even though the volume does not, and that is what makes rule 7’s waterproof jacket and waterproof trousers obligatory rather than cautious.
Two cautions on the cold. The mean daily minimum is not the overnight low — it is the average of the daily minima, and the frost days in the same column prove the distribution reaches below zero. And frost in May is worst where it is driest: Altnaharra No 2 averages 5.27 days of air frost against Kinlochewe’s 1.70 days. The clear northern nights are the cold ones, which is why rule 7’s unrated “sleeping bag” is not a trivial requirement.
The window is narrow at both ends, for two unrelated reasons
When to ride it, and why
DECLAREDLate spring, for two reasons the organiser states together: settled weather, and the midges not having started.
“The best time to attempt the route is late spring when the weather can often be relatively settled and the midge season may not have properly started.”
Highland Trail 550 organiser · source · read
The group start
DECLAREDLate May, which is why May is the month the weather figures below are for.
“The suggested date for the group start is in late May”
Highland Trail 550 organiser · source · read
Why the late season closes, and it is not the weather
DECLAREDThe organiser advises against winter, and against August to October because of the stag stalking season on the private estates the route crosses, which depend on stalking for income. So the window is narrow at both ends for two unrelated reasons: midges and settled weather close the early end, deer stalking and estate income close the late end.
Stated rather than quoted. This came back as our fetcher’s paraphrase rather than as a quoted string, unlike rules 1–8, so the fact is the organiser’s and the wording is not yet verified verbatim.
Highland Trail 550 organiser · source · read
How long it is, and why nobody quite agrees
Distance
DECLARED550 milesFive hundred and fifty miles, which is also the event’s name.
A round number in the event’s title rather than a surveyed length. Converting it to metres would dress a name up as a measurement.
Highland Trail 550 organiser · source · read
Total climbing
DECLAREDover 16 kmOver sixteen thousand metres — the organiser’s floor, not their figure.
“over 16000m of climbing”
A lower bound in the organiser’s own wording. Rendering it as a precise total would silently convert their floor into our claim.
Highland Trail 550 organiser · source · read
Distance
- 550 milesDECLARED
Highland Trail 550 organiser · source · read
- 545 milesREPORTED
Trailforks · source · read
Five miles apart, and neither states which version of the route it measured. The organiser confirms that a widely linked third-party guide describes an older route, which makes every third-party figure suspect and is still not evidence about this one.
Total ascent
- over 16,000 m — a floorDECLARED
Highland Trail 550 organiser · source · read
- 48,994 ftREPORTED
Trailforks · source · read
This is sharper than a disagreement about an estimate. Over 16,000 m is over 52,493 ft by our own conversion, so the third-party figure sits 3,499 ft below the number the organiser says the route exceeds. These cannot both be right about the same route file.
The current route file
DECLAREDThe organiser does not publish the current GPX for download. It is released in exchange for a donation to their Trees for Life grove followed by an email request, and the organiser separately says a widely linked third-party guide covers an older version of the route.
Highland Trail 550 organiser · source · read
Elevation band
DECLAREDThe terrain runs between sea level and about 800 m. The organiser names a band and never a summit, which is the more useful fact anyway: a sea-level-to-800 m loop in the Highlands is a statement about repeated climbing, and that is what the ascent floor is really saying.
“between sea level and 800m”
Highland Trail 550 organiser · source · read
Bothies: named, linked, and nothing else
The bothy network is a real fact about this route and the obvious thing a Scottish route page would carry. We carry a link and nothing more, and the reason is worth stating rather than hiding behind a gap.
- mountainbothies.org.uk
- The bothy network is a real fact about this route and the obvious thing to want on a Scottish route page. The Mountain Bothies Association disallows ClaudeBot, GPTBot, CCBot, Google-Extended, Amazonbot, Applebot-Extended, Bytespider and meta-externalagent by name; sets Content-Signal ai-train=no, use=reference; reserves rights expressly under Article 4 of EU Directive 2019/790; and 403s. So this page names the network, links to it, and carries nothing else — no locations, no conditions, no prose. We did not request a page from them even once.All four registers at once · their page
What we could not source
8 things a page about this route would normally state, that we could not source. They are listed rather than filled in.
- Whether the water is plentiful and the burns are drinkable
- The single largest gap on this route, and the thing every incumbent asserts. No organiser page addresses water at all: not the rules, not the route page, not the home page. The one mention anywhere is advice to refill bottles from a tap instead of buying bottled water, for a plastic-reduction reason — which is not a statement that the route has plentiful water and not a statement that streams are safe to drink. Public guidance on Scottish private water supplies is about boreholes and springs piped to properties, which is a regulated supply serving a house rather than a hill burn, so citing it here would look sourced and would not survive being checked.
- A declared high point
- The organiser publishes a band — sea level to about 800 m — and never a summit. A third party’s route file reports a 772 m maximum, which sits inside that band; that is mild corroboration and not a licence to publish a route specification derived from a file of unknown vintage.
- Any mass, volume or temperature rating for the rule 7 kit
- Rule 7 names items only. No sleeping-bag comfort limit, no insulation weight, no hydrostatic head, no lumens and no runtime.
- Resupply points and the distance between them
- Not on any organiser page we read, on a route whose whole hazard is remoteness.
- Bothy locations, conditions or availability
- Deliberately not sought. See the refusal above.
- The overnight low as a distribution
- The long-term averages give a mean daily minimum and a frost-day count, and nothing else. The mean minimum is not the cold night — the frost days are the honest proxy, and that is all there is.
- Midge season dates
- The organiser says the midge season "may not have properly started" in late spring and gives no dates. Nothing else we read supplies them.
- Wind
- The long-term averages pages surface temperature, rainfall, frost and sunshine. Wind was not on the pages we read.
The other two routes, and why their answers differ
Both halves, for your own bike
Rule 7 tells you what has to be on the bike. Which of it will physically mount depends on your frame, and the three above are reference shapes rather than anybody’s bicycle. A photograph of the drive side produces yours.