EPSG
National Geographic Institute of Spain (IGN), http://www.ign.es
2020-06-27
Geodesy, engineering survey, topographic mapping.
Orthometric heights.
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "VerticalReferenceFrame", "name": "El Hierro", "scope": "Geodesy, engineering survey, topographic mapping.", "area": "Spain - Canary Islands - El Hierro onshore.", "bbox": { "south_latitude": 27.58, "west_longitude": -18.22, "north_latitude": 27.9, "east_longitude": -17.83 }, "id": { "authority": "EPSG", "code": 1284 } }