Hi there,

Does anyone know a good data-source of bounding information for countries, states, counties, cities, etc?

Ideally, this information might be on Wikidata, https://www.wikidata.org/wiki/Property:P1332 Co-ordinates of northernmost post https://www.wikidata.org/wiki/Property:P1333 Co-ordinates of southernmost post https://www.wikidata.org/wiki/Property:P1334 Co-ordinates of easternmost post https://www.wikidata.org/wiki/Property:P1335 Co-ordinates of westernmost post

-- but there's very little there yet.

I'm asking because the big 50,000 map georeferencing of the British Library "Mechanical Curator" maps should be going live in the next two to three weeks.

A project target would be to get a back-end in place that can upload maps to Commons *with appropriate categories* within 24 hours of an image being georeferenced by a volunteer.

A batch of 3000 maps already geo-referenced is available as a test set.

I have had some success using Nominatim on the centre point plus points 40% of the way to each corner, to identify continents, countries, states and counties that the map appears to be contained within.

But it would be good to know whether it is a map of a whole county, or a map of several counties, or a map of a large feature within a county.

At the moment, my Nominatim script is a bit cautious, especially for areas surrounded by sea -- eg Cornwall, Devon, Italy. It's not so good at recognising that the map is a bit smaller than the encompassing continent/country/region/county. It would be good to be able to compare the bounding boxes, to determine how much of the county is in the map, and vice-versa.

Does anyone know if such data is readily obtainable? Or if there are good online services from which it could be got on the fly?

Cheers,

James.