Can you use Garmin Connect to map, now? It didn't use to have that capability, and I sure don't see it now.

I find MapMyRide to be generally the easiest place to create a .gpx, although I'm not a huge fan of the "new" interface. Ridewithgps has other features, including a MUCH better elevation profile. But especially if you're looking for public routes that other people have uploaded, MapMyRide probably has more than any other, at least in the USA.

One of those two ought to do it for you.



ETA - cc, do you have to use bikeroutetoaster and Training Center to upload a .gpx to the 800, the way you have to with the newer Forerunners? That is a PITA. But I didn't think you had to do that with the GPS units that have native mapping capability.