Geo mapping - how to?

I need to develop an application where I will display statistics o开发者_Python百科n a map at county / town level. I had a look at the Google API, but the Geo Mapping is only at the country level. Has anyone seen a geo mapping API which can colour area of a map at county or town level?

Thanks a lot.

You can use OpenLayers if you can get the county polygon data in the right form - GML would do nicely, and there are tools to convert from Shapefile and other common geo-polygon data formats to GML (ogr2ogr from the GDAL package).

All Free and Open Source.

The developer of jVectorMap (a jQuery plugin) has an example with various German states. Like OpenLayers, you'll need to somehow get county polygon data in the right form to use for jVectorMap. You might consider contacting the jVectorMap developer to ask if there's a straightforward way for you to accomplish this.

On the d3.js example of a Choropleth chart, Mike Bostock mentions: "U.S. state and county boundaries from the U.S. Census Bureau, simplified using GDAL and MapShaper." These two tools (GDAL and MapShaper) may help.