Route Planning?
I have a "Garmin Montana 610" and would like some suggestions about route planning. I would like to map a route and transfer it to my Garmin. I ride motorcycles and like to travel on backroads "gravel" as much as possible but what I have shows what road I'm on but that's all.
You need to install a routable map for starters. Some people use the free OpenStreetMap available here:

I suppose the quality varies depending on where you are, but IMO they leave a lot to be desired in my area. Since they're free, you can always try them and decide for yourself.

IMO Garmin's own maps are going to be the best choice for your Montana in most places, I purchased their City Navigator map for my Montana 600 a few years ago. Unfortunately, you can't get "lifetime" City Navigator maps for a Montana, they are one-time purchases and you have to buy a whole new map if you want to update later. The full North America version is $80 or you can get the "Lower 49" US version for $60.

Garmin's Topo 24K maps use the same roads and are also routable, but each product only covers a few states and costs $100

For route planning, you can use Garmin Basecamp, which is free. Connect your GPS to your computer and it will access the maps so you can use them for route planning.

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