OpenStreetMap

Adrion's Diary

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GIS data for listed buildings, scheduled monuments (e.g. interesting tumuli) and more can be downloaded from https://historicengland.org.uk/listing/the-list/open-data-hub/, and here are some observations based on my experiments with geoJSON and shapefiles.

The data is under the Open Government Licence so OK for editing OSM.

The download can be kept to a manageable size by enabling “Filter as map moves” in the filter menu (funnel symbol) and then “Toggle filters” when selecting the download.

Vespucci can display a geoJSON layer, show object attributes, and even create preliminary OSM objects from them. But it didn’t work here. I discovered that the downloaded geoJSON uses EPSG:3857 (projected coordinates) whereas the geoJSON standard is EPSG:4326 (latitude and longitude).

An easy way to do the conversion was to go to https://mapshaper.org, “upload” the file (actually it’s processed on the client side), open the console and enter:

-proj from=EPSG:3857 crs=EPSG:4326

and then export.

The resulting geoJSON works well in Vespucci. You can either “Add GeoJSON layer” from the layer menu, or select it in a file manager and open with Vespucci. I could do the whole process above on a modest android tablet.

OSM tags worth thinking about include:

  • heritage = 2
  • heritage:operator = Historic England
  • ref:GB:nhle =
  • listed_status =
  • wikidata =

Note that I’m not suggesting adding anything to the map that can’t be located with a ground survey, and certainly not blindly copying polygons (aside from considerations of verifiable ground truth, these may include a protective buffer around the feature).

I also experimented with OruxMaps version 9.6.3GP; menu Map_tools>Load KMZ/KML/SHP Overlay to show the features over any map including OSM (eg. from OpenAndroMaps). It displays the transformed geoJSON but doesn’t show the attributes when you tap on an object. However, repeating the data download using Shapefile instead of geoJSON, again transforming with mapshaper (you can upload a zipped folder containing the .shp and its auxiliary files), seems to work perfectly.

I hope that helps someone!