Wednesday, July 27, 2022

Give Me Geodata

Hans Hack's Gimme Geodata just might make it onto my bookmark list of mapping tools I use on a near daily basis (a very short list which currently consists of Leaflet, and overpass turbo). 

Gimme Geodata is a very easy to use tool for quickly downloading OpenStreetMap boundary data. To use the tool you just need to click on an interactive map to indicate your area of interest. Gimme Geodata will then list all the boundaries (and any other polygons such as administrative areas, parks, houses etc) within which your clicked location falls. For example if I click on Baltimore on the Gimme Geodata map it provides me with a hierarchical list of administrative areas, including Baltimore, Maryland and the United States.

You can then click on any of the provided boundaries to download or copy the data in GeoJSON form. Gimme Geodata is therefore a very easy to use tool for quickly finding and downloading geographical data from OpenStreetMap. For example if I wanted to create a map of all the parks in my local town I could grab the boundary data for each park by simply clicking on it on Gimme Geodata and then downloading the data to my computer.  

Gimme Geodata is very similar to MySociety's MapIt. If you provide MapIt with a latitude and longitude it will then list all the administrative areas that it falls within. You can then download the boundaries as Geometry (JSON), WKT, GeoJSON or KML data.

MapIt also features a number of query parameters which allow you to also find all the boundaries touching, intersecting or overlapping your requested location. The MapIt API includes a number of other features which allow you to define and refine the data you wish to download in lots of different ways. For example this query finds all the admin areas starting with 'Trump' -

No comments: