leaflet-tilelayer-swiss

Leaflet.TileLayer.Swiss

Leaflet.TileLayer.Swiss is a Leaflet plugin for displaying national maps of Switzerland using map tiles from Swisstopo. This plugin is not affiliated with or endorsed by Swisstopo.

Requires Leaflet version 1.x

Demo

The quick start example is a good place to start.

There is also a list of all available map layers and a slighly more advanced example.

Usage

Prerequisites

• Leaflet library, see Leaflet quick start guide
• Swisstopo web access if you want to publish your application

Quick start

Include this plugin after the Leaflet JavaScript file:

<script src="https://unpkg.com/leaflet-tilelayer-swiss@2.0.3/dist/Leaflet.TileLayer.Swiss.umd.js" crossorigin
        integrity="sha384-bHBj6G7VG9PdK9RKiYRLB6PRJMpw8sRhZks+TGHAO3zgz8c9Z+lAaDmbv/zsQI3j"></script>

Put a div element with a certain id where you want your map to be:

<div id="mapid"></div>

Make sure the map container has a defined height, for example by setting it in CSS:

#mapid { height: 400px; }

Set up the Swiss map:

// Create map
var map = L.map('mapid', {
  // Use LV95 (EPSG:2056) projection
  crs: L.CRS.EPSG2056,
});

// Add Swiss layer with default options
var swissLayer = L.tileLayer.swiss().addTo(map);

// Center the map on Switzerland
map.fitSwitzerland();

// Add a marker with a popup in Bern
L.marker(L.CRS.EPSG2056.unproject(L.point(2600000, 1200000))).addTo(map)
  .bindPopup('The old observatory')
  .openPopup();

Options

Options are shown with their default values.

L.tileLayer.swiss({
  // Coordinate reference system. EPSG2056 and EPSG21871 are available.
  crs: L.CRS.EPSG2056
  // Image format (jpeg or png). Only one format is available per layer.
  format: 'jpeg',
  // Layer name.
  layer: 'ch.swisstopo.pixelkarte-farbe',
  // Minimum zoom. Levels below 14 exist for technical reasons,
  // but you probably do not want to use them.
  minZoom: 14,
  // Maximum zoom. Availability of zoom levels depends on the layer.
  maxNativeZoom: 27,
  // Timestamp. Most (but not all) layers have a 'current' timestamp.
  // Some layers have multiple versions with different timestamps.
  timestamp: 'current',
  // Map tile URL. Appropriate defaults are chosen based on the crs option.
  url: 'https://wmts{s}.geo.admin.ch/1.0.0/{layer}/default/{timestamp}/2056/{z}/{x}/{y}.{format}'
});

A list with all available layers and corresponding options is available here.

Coordinate reference systems (CRS)

Two CRS are commonly used in Switzerland:

• New (default): LV95 (EPSG:2056)
• Old: LV03 (EPSG:21781)

In order to use EPSG:21781, both map and layer CRS have to be adapted:

var map = L.map('map', { crs: L.CRS.EPSG21781 });
var swissLayer = L.tileLayer.swiss({ crs: L.CRS.EPSG21781 }).addTo(map);

map.setView(L.CRS.EPSG21781.unproject(L.point(600000, 200000)), 16);

Swisstopo web access

You will need to register with Swisstopo if you want to publish an application that displays base map layers from Swisstopo.

If you have your own domain (e.g. example.com), you can sign up for Swisstopo web access. There is a free tier (no credit card required) limited to 25 gigapixels of map tiles per year, and there are paid options if you need more.

If you do not have your own domain, sadly you are out of luck, as Swisstopo currently does not provide any other way to sign up for access to the map tiles.

The usage restriction is enforced by checking the HTTP Referer header, so your application will automatically work once you have signed up.

You will probably also want to test your application locally before publishing it. localhost is also accepted as a Referer, so if you run a local web server, you should be able to access the map tiles.

Swisstopo also provides some overlay layers which are freely accessible, see list of layers and their accessiblity.

Attribution

Swisstopo, like most map tile providers, requires that you display a copyright attribution below the map.

This plugin adds a map attribution which links to Swisstopo, the same as it is done by the official Swisstopo API.

The terms of service suggest using the phrase "Source: Federal Topographical Office (agreement no.)", which you may want to use if you have an agreement number from Swisstopo. You will probably get such a number if you sign up for paid access to the map tiles.

License

This plugin is licensed under the MIT license, see the LICENSE file.

Acknowledgements

Thanks to Swisstopo and the Geoinformation Act for providing excellent geodata.

Thanks to @procrastinatio whose blog post taught me how to use Swisstopo layers in Leaflet a few year ago.

See also

• Documentation and source of the official Swisstopo API based on OpenLayers 4
• Terms of service for the free and paid tiers of Swisstopo