This page is the public source and licence record for the exact Swiss Central Alps database distributed by Grat (formerly Cairn). The existing /cairn path and Cairn schema name remain for compatibility. The downloadable files are immutable: the directory is keyed by the package SHA-256 and will not be overwritten.
Current v1 map release
A compact, machine-readable offline database prepared for iPhone and Apple Watch. It is a field aid, not a guarantee of trail conditions, route safety, or official surveying accuracy.
v2026.09.05
Region
Swiss Central Alps
Data date
5 September 2026
Coverage
45.95–47.30° N · 7.05–9.03° E
Package size
11,405,701 bytes · 10.877 MiB
Features
15,863
Format
Cairn schema v1 · canonical JSON
SHA-256
Exact release files
The package checksum below is for the transport file. The canonical checksum is stored inside the manifest and is independently verified when Grat installs the map.
The .cairnmap file above is the complete machine-readable adapted database that Grat distributes. The database rights in the OpenStreetMap-derived database are offered under the Open Data Commons Open Database License 1.0. You may copy, use, modify, and redistribute that database subject to the ODbL and its attribution and share-alike conditions. The public package link is the direct source download; no account or request is required.
This ODbL grant does not relicense third-party contents that retain separate terms, including Copernicus-derived contour data, nor does it apply to Grat application code, branding, or other non-database assets.
OpenStreetMap Alps extract published by Geofabrik, snapshot 2026-09-05T20:22:06Z. Grat clips the supported rectangle, selects the signed hiking network and relevant supporting layers, then merges, simplifies, and quantises the geometry for offline use.
Grat derives contour lines from the Copernicus DEM GLO-30 Public 2021 release. The build resamples the elevation model to about 90 metres and retains simplified 200-metre contours of at least 500 metres for the Watch package.
Grat validates the declared byte size, schema, bounds, feature identifiers, and canonical checksum before installation. The source ledger records every pinned source file; the private application repository contains the deterministic build tooling but no source credentials. The public package itself is the source form of the distributed adapted database.
Downloading a file makes a normal HTTPS request to 084817.xyz, delivered by Vercel. Grat does not attach an account, hike or Health record, precise GPS location, or advertising identifier. Vercel can process ordinary request and security metadata—including IP address and IP-derived city and country, request time and path, User-Agent, related headers, and edge or firewall diagnostics—for delivery, security, and reliability diagnostics. See the privacy policy for details and official Vercel links.
If a credit, source, or licence record appears incomplete, contact Loadchange and identify this release by its package SHA-256.