As noted above, you can use the free version of RWGPS to load routes into your Edge. One feature of RWGPS that I like is the ability to choose among different maps. I generally use the OSM-Cycle map for rides where I live.
I also have the RWGPS app on my phone. I find it useful when I am exploring and get lost. I can use the app and change maps until I find one with the road or trail I am on and use it to plot my escape. It works much better than Google or Apple maps.