U.S. National Parks
- pulled from Data.gov as a zipped shapefile on 4/11/2015
- simplified geometry in Quantum GIS (Vector menu -> Geometry tools -> Simplify Geometries)
- simplified the zipped shapefile down from about 15mb to 373KB
- then filtered to only show
UNIT_TYPE = National Park
- saved as geojson from QGIS
- converted to TopoJSON with a final file size of only 34KB!
- UPDATE: Apparently all of the above conversion and simplification could have been accomplished via the TopoJSON CLI
Useful ogr2ogr and TopoJSON commands more info here and here
ogr2ogr -f GeoJSON -t_srs EPSG:4326 natparks4326.geojson .\NationalParks4.geojson
topojson -o natparks.json .\natparks4326.geojson -p UNIT_CODE,UNIT_NAME,UNIT_TYPE
Awesome!