How we verify

Trust is the product. Every numeric fact on a trail page can carry a source and a last-checked date. When we cannot source a value, it stays unknown, Unverified, or unpublished. That is the bar we used for the Switzerland pilot and the one we apply everywhere else.

We use AI tools to help find and organise official sources. Every figure on the site carries its source and the date we read it, and one of four labels: Verified, Reported, provisional, or Unverified. Approximate or computed figures are marked provisional. Where no source exists, we leave the value blank instead of guessing.

Verified and reported

A claim is published in one of two blocks, or it is left off the page. Verified means a dated primary source: a park authority, land manager, or the official issuer. Reported means a named secondary source, including OpenStreetMap geometry under the ODbL. The two blocks are not mixed, and a reported figure is not styled as verified. If a section has no source, that section is absent. There is no general-knowledge tier. Permit fees stay on the permit record; the trail page links to it instead of copying the tariff. Geometry credited to OpenStreetMap carries the contributor attribution on the field and in the site footer.

Distance

The DataPoint is the planar 2-D length of the stored route. For an OSM corridor that is osm:relation:<id> after the snaps the record discloses — not 3-D distance along the slope, not a GPS tracklog, and not an average of blogs. The official kilometre is the cross-check: the OSM line must sit within 3% of that figure, or we do not publish the route. When official pages disagree with each other, we leave the disagreement in view. More on why published lengths clash: How long is the trail, really?.

Verticals

Ascent, descent, and high/low points are sampled from Copernicus GLO-30 along the stored line. The current method is derived:glo30/v1: one sample at each stored vertex, no extra densification, and a 10 m hysteresis window on cumulative gain and loss. v1 does not smooth the profile. Sample spacing is the stored vertex spacing, and the only threshold is that 10 m window. That version is the source string on the four elevation facts, so the signed record names the method as well as the number. A change in spacing, hysteresis, or densification is /v2 and a new signature. Those figures remain provisional until a field check. Cumulative gain runs noisy-high against a smoothed GPS track; we do not overwrite it with a rounder official ascent.

Permits and fees

A permit is quoted from an official page, or it is Unverified. We never invent a fee. A fee read on the issuer’s own page is public on the trail page, with the issuer and the date. Fees that are only reported, or not yet sourced, stay behind login and are not given a number in the public HTML.

Safety stays public

Hazards, season, and difficulty (SAC and YDS plus a plain label) are not gated. Conditions change; a provisional mark means the figure still needs a field check, not that the public page is allowed to go silent.

Honest hard-stops

If OpenStreetMap cannot supply a connected hiking line within 3% of the official kilometre — branched superroutes, way-bags, incomplete stages, border-bisected stages with no in-country figure — we hard-stop. We do not stitch fragments, densify a transport chord into walking, or publish a stub. Switzerland’s ViaJacobi, Jura Crest Trail, and Alpine Passes Trail are the national examples: named here, not given invented kilometres. The verified Swiss set is grouped on Hiking in Switzerland.

Verified vs provisional

Verified on a DataPoint means the figure cleared its source bar and is not flagged provisional. A * or the word provisional means it still needs a field check. A schematic length can be stored and still be labelled not walking distance.

Trans Swiss Trail — verified walking km, labelled boat

The 510.1 km is walking. Official stage 7 starts with a scheduled boat across Lac de Neuchâtel because there are no suitable trails. That crossing is logistics, not walking distance, and is not in the DataPoint. ViaGottardo is the same pattern on Lake Lucerne: 322.1 km walking, official boat on stage 7 labelled and excluded.

Walker's Haute Route — schematic caveat

No single connected Walker’s Haute Route hiking relation resolved, so the stored line is pin-to-pin through named OSM nodes (122.6 km), not a walking path. Published walking figures on the record remain cross-checks. Everest Base Camp in this catalog is the same class of honesty — see How long is the trail, really?.

Via Alpina — provisional elevation

Length on Via Alpina is the Reported OSM 2-D line (379.5 km). The GLO-30 ascent stays provisional. We do not round it to the official table and call the job done.

What this is not

This is not a route planner, and it is not a claim that every trail in the world has been verified. It is a sourced method: Switzerland’s published national and regional records in this catalog cleared the bar; other countries are a mix of Reported OSM corridors, labelled schematics, and honest gaps. Use this page as the reference for how the data works.

Also in this desk: Verify a trail record · How long is the trail? · Hiking in Switzerland · Permit & season calendar · Switzerland country index.

Questions