My last post went into a lot of detail on setting things up to solve edge covering problems. Despite the torrent of words I threw at the topic, I wanted to highlight the step of extracting map data from OpenStreetMap for a city. As with many of my posts, this one is motivated by a question on the OR-Tools mailing list. The original poster asked about generating walking routes to conduct a door-to-door survey of residents of Port-au-Prince, Haiti.