# ch_swisstopo_README.txtThe files in this section result from the conversion of datasets originatingfrom [Swisstopo](ttps://www.swisstopo.admin.ch)## Included grids### Switzerland: LV03 (system CH1903) -> LV95 (system CH1903+)*Source*: [swisstopo](https://www.swisstopo.admin.ch/en/knowledge-facts/surveying-geodesy/reference-frames/transformations-position.html) *Format*: GeoTIFF converted from NTv2.0 (.gsb) *License*: [Creative Commons CC0 1.0 Universal](https://creativecommons.org/publicdomain/zero/1.0/legalcode) *Credit*: (c) 2007 swisstopoRecommended to transform from Swiss reference frame LV03 (system CH1903, EPSG:21781) to Swiss reference frame LV95 (system CH1903+, EPSG:2056).LV95 is aligned to ETRF93, but shifted by several 100 meters.CH1903+ is the official reference system for federal surveying and for all national geobasis data regulated by federal law since 2017.CHENyx06a.gsb gives corrections (distorsions between LV03 and LV95) in CH1903, CHENyx06_ETRS.gsb gives the corrections in ETRS.Several transformation services are available on https://www.swisstopo.admin.ch/en/maps-data-online/calculation-services.html(web forms and REST web geoservices) to support the exact transformation procedure between CH1903 and CH1903+using the REFRAME algorithm (finite element transformation).The difference between the grid and finite element transformation is on a level of below several millimeters.* ch_swisstopo_CHENyx06a.tif* ch_swisstopo_CHENyx06_ETRS.tif