I'd like to edit an SVG map that I downloaded from OpenStreetMaps such that it has border lines around the different Census Block Groups in the city. I'd like to be able to shade the various census block groups different colors dependent on some census data. I tried looking through the SVG file I had downloaded myself, but it has literally thousands of lines and I was unable to find a way to get a start on it. This is, ultimately, what I'd like it to look like: http://i.imgur.com/JXmBbOB.png I'm not looking for someone to do this for me of course, just trying to find a way to meaningfully manipulate the SVG such that it has the block groups represented. Could anyone help get me started?