I'm going to be riding in the Alps, crossing back and forth between Italy and France. I plan on using my Garmin Edge 800, but I discovered that the maps for Italy and France are on different MicroSD cards. It isn't really practical to switch cards in the middle of a ride. Does anyone know what happens when you literally ride off the map you have loaded? Will I still get a usable route to upload to Garmin Connect or Strava?
If you don't switch cards it just means that you won't be able to see where you are on the detailed street maps on the 800 once you ride off the edge of the first map. But the unit will still be recording your position so when you later upload the data to Strava or other website the entire path you took will be displayed properly.
It also depends of if you want the unit to navigate the route and give turn prompts. It needs a routeable map resident to do that. Having purchased those maps on SD cards, I think you're hosed in that regard. FWIW I have a Garmin SD card map that covers all of EU. https://buy.garmin.com/shop/shop.do?cID=253&pID=6299
You can probably find open source maps that will do the trick for you. Here are a few related links: