[retzkek]

I refer to Strava and RideWithGPS heatmaps whenever planning a new cycling or running route, and they are very useful, but they still need vetting (satellite and street view mostly) since 1) people have different tolerances for safe/comfortable interactions with traffic, and 2) road race data is often mixed in (despite users being able to tag races), which frequently are on (closed) roads you wouldn’t want to be on otherwise.