Distance is the least useful number in a trail description. Two walks of the same length can differ by five hours, and the numbers that explain why are usually printed smaller.
Ascent is the number
A flat 20 km walk is a long day on easy ground.
A 10 km walk with 1,200 metres of climbing is a hard mountain day.
Any description giving only distance is omitting the figure that determines the effort. Look for total ascent, and for the profile if it is published — 600 metres spread over a day is different from 600 metres in one relentless push.
Naismith's rule
The standard planning estimate:
One hour per five kilometres, plus an extra hour per 600 metres of ascent.
It assumes reasonable fitness, good ground and no stops. In practice most walkers add a third or more for breaks, rough terrain, navigation and descent.
A 14 km route with 900 metres of ascent works out at about four and a half hours by the rule, and about six in reality.
What a published time assumes
Guidebook and signpost times vary in what they include.
Swiss yellow signposts give walking times to a national standard and are accurate to within minutes for an average walker — they assume no stops.
Guidebook times are usually moving time only.
Operator times on commercial routes frequently include stops and are more generous.
Check what the source is doing before trusting the figure.
Terrain, which the words describe imprecisely
Path — maintained, obvious, straightforward.
Mountain path — uneven, rocky, requiring sure footing, possibly with drops.
Scramble — using hands. Graded 1 to 3 in the UK, where grade 3 is close to climbing and a rope is reasonable.
Exposed — a fall would be serious. This word is doing heavy work in any description and should stop anyone uncomfortable with heights.
Alpine route — may involve glacier, snowfield or climbing, and needs equipment.
Grading systems do not transfer
They vary by country and are not interchangeable.
| System | Note |
|---|---|
| Swiss | Yellow / white-red-white / white-blue-white |
| French | GR waymarking, plus a separate difficulty scale |
| US | Easy / moderate / strenuous, applied loosely |
| UK | Scramble grades 1–3, plus general descriptions |
| Japan | Numeric difficulty and fitness scales by prefecture |
Read the local key rather than assuming a moderate in one place matches a moderate in another.
The descent problem
Descent is not much slower in time and is considerably harder on knees and more dangerous for falls. Most hiking injuries happen on the way down, when people are tired and moving faster.
Poles help substantially and are the single most underused piece of equipment.
Where a route allows it, descending the gentler side is worth planning for.
The turnaround time
Decide before starting what time you will turn back regardless of how close the summit is.
Most mountain incidents involve people continuing past the point where the remaining daylight, weather or energy supported it.
The summit is optional. Getting down is not.