Generalised boundaries K4 — communes, cantons, lakes and national border
bfs-generalised-boundaries
- Publisher
- OFS/BFS
- Access method
api- Table id
ch.bfs.historisierte-administrative_grenzen_k4 / historisierte-administrative_grenzen_k4_2026-01-01- Licence
- opendata.swiss terms of use "terms_by_ask": "Open use. Must provide the source. Use for commercial purposes requires permission of the data owner."
- Coverage
- Geography Switzerland — 2110 communes, 26 cantons, 22 large lakes, national border · referenceDay commune state of the latest item (1 January 2026 on 2026-11-01) · from 2026-01-01 · to 2026-01-01
- Gaps
- Only the latest commune state is kept (the collection has every state since 1850). Districts are not fetched. Lakes smaller than those in the K4 lake layer are not drawn.
- Used on
- STORY-04, AGORA-20, AGORA-22
- Known limits
- Generalised geometry for thematic maps at 1 : 500 000 and smaller (BFS): shapes are simplified, so areas measured on them differ from the official areas; Votara never computes areas from these shapes (densities use bfs-land-use-communes). AREA_HA is the area attribute of the BFS file, not used for calculations. The unlisted asset kanton_2056.geojson served WGS84 coordinates on 2026-10-31; the fetcher uses the listed kanton_vf layer and refuses non-LV95 files. Licence "terms_by_ask": free for non-commercial use with the source named; commercial reuse of the maps needs the permission of the BFS.
- Verification
- verification date: 2026-11-01 · method: Fetched from data.geo.admin.ch (STAC item historisierte-administrative_grenzen_k4_2026-01-01, layers gemeinde_vf, kanton_vf, see, land in LV95). The 2110 commune features match the BFS commune register (bfs-communes, agvchapp snapshot of 2026-10-31) one to one in BFS number, name and canton; the AREA_HA attribute of Bern (351) is 5162 ha, the "Gesamtfläche" of 51.62 km² in the BFS Regionalporträts 2021. · checkedValue: 2110 communes = register (0 differences in number, name, canton); 351 Bern AREA_HA 5162 ha = 51.62 km² · checkedAgainst: https://dam-api.bfs.admin.ch/hub/api/dam/assets/15864450/master
- Processed file
- data/processed/bfs-generalised-boundaries.csv
How current is this data?
- Freshness
- Up to date
According to its update rhythm, no newer edition is expected yet.
- Period covered
- Not a time series
- Last change of the data
- Last check of the source
- Update rhythm
- Yearly
Ledger note (in English): Yearly, with the commune state of 1 January (published in early February); extra items when communes merge during the year (e.g. 2025-04-06).
- Votara checks the source
- Every week, and every day from 3 days before to 14 days after an announced publication date
The state is computed each time the site is built; this page shows it as of . Results of the accuracy checks
Transformations
- STAC API (data.geo.admin.ch): list the items of collection ch.bfs.historisierte-administrative_grenzen_k4 since 1 January of last year, take the item with the latest datetime, download its LV95 GeoJSON assets gemeinde_vf (communes without the large lakes), kanton_vf (cantons, same), see (lakes) and land (national border). Script: scripts/fetch/bfs-generalised-boundaries.ts
- Coordinates to Votara's map frame, a linear scale of LV95 (planar, metres; no projection): x = (E − 2480000) ÷ 100, y = (1300000 − N) ÷ 100, rounded to whole units of 100 m (src/lib/geo/map-frame.ts). Per ring: repeated and exactly collinear points dropped, rings that vanish at 100 m dropped (src/lib/geo/map-path.ts). No other simplification: the K4 geometry is already generalised by the BFS, and borders shared by two communes stay identical.
- One SVG path per feature (one subpath per ring, holes included, drawn with fill-rule evenodd); bounds in map units; the published centre point E_CNTR/N_CNTR in map units; AREA_HA copied as published.