
Ask HN: How are mapping organisations notified of land border changes? - OJFord
In the news today is a land-exchange between Holland and Belgium [0].<p>How are - if indeed they are - the Ordnance Survey, Google Maps, and other entities notified of the precise changes, coordinates that allow them to recreate the division in their maps?<p>[0] - http:&#x2F;&#x2F;www.nytimes.com&#x2F;2016&#x2F;11&#x2F;28&#x2F;world&#x2F;europe&#x2F;belgium-netherlands-land-dispute.html
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knz
Great question.

Most countries have a mapping agency/authority
([https://en.wikipedia.org/wiki/National_mapping_agency](https://en.wikipedia.org/wiki/National_mapping_agency)).
I've always assumed that each country defines it's own spatial boundary
defined by the relevant legal agreements that define a country. Third parties
such as Google presumably use whatever each country provides and try to stay
out of any disputes ([http://qz.com/218675/here-are-the-32-countries-google-
maps-w...](http://qz.com/218675/here-are-the-32-countries-google-maps-wont-
draw-borders-around/)).

As far as updates, someone probably just has an annual calendar reminder to
pull the latest shapefile for each territory or from a central authority (UN?
National Geospatial Agency?)! The geographer in me is mildly amused at the
thought of someone in Belgium making a pull request to The Netherlands related
to updating a boundary.

If you're interested in questions like this, I highly recommend the FOSS4G
conferences ([http://2017.foss4g.org/](http://2017.foss4g.org/)). Many of the
big names in GIS attend and can likely give an authoritative answer on
questions such as this.

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techjuice
Many countries get their information from their own national imagery and
mapping agency. For the United States it is the National Geospatial-
Intelligence Agency or NGA. For countries that need help with this information
or need higher quality imagery they normally can get assistance from the NGA
through their government and commercial partnership arrangements.

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timeiscoffee
Relevant article regarding border controversies around Crimea

[https://www.gislounge.com/cartographers-respond-border-
chang...](https://www.gislounge.com/cartographers-respond-border-changes/)

> Johnson noted that in the United States, most map making companies take the
> lead from the State Department in determining when to update border changes
> on their maps.

