c5360704_or_the_Garmin_Edge_Touring_GPS__recommended_for_route_planning
[Site] Google Earth
I’m not already a Google Earth user, so it seemed like a lot to learn and download. I will just note that if you use Google Earth already and know how to build a route on it, you can apparently export the route to a KLM file. Then you can use one of the GPS conversion utilities listed above to change it to a GPX or TCX file, and transfer it to your device.
Jennifer and Zach's Adventures » Planning Rides for the Garmin Edge Touring GPS
Why not recommended for route planning