A fellow attendee at the Open Data Day Toronto event hosted by Urban+Digital Toronto was wondering how to display Toronto neighbourhood data on a map that she was working on. I couldn’t find any GeoJSON of the neighbourhoods out in the open, so I grabbed a shapefile from the City of Toronto Open Data Portal – Toronto Neighborhood Planning Areas.
To export it to GeoJSON I used the ogr2ogr tool from GDAL (Geospatial Data Abstraction Library).
$ ogr2ogr -t_srs EPSG:4269 -f geoJSON Neighbourhoods.json Neighbourhoods.shp
The resulting GeoJSON file was 1.4M in size. That’s a bit big to be sending down to the browser, so I used the Simplify geometries tool in Quantum GIS (QGIS) and then re-exported to GeoJSON. The resulting file is a manageable 308K. It still looks good, so it could be shrunk down even further if needed.