Definitely call the park and talk to them if you’re going to be in the park itself.
This time of year is Glaciers peak season, and they tend to be pretty full. My wife and I did a “last minute” trip to glacier where we planned our backcountry route over a month in advance, and we were told we lucked out even being able to get a backcountry permit.
I may be totally wrong on this, but from my limited knowledge of glacier you probably won’t be able to take your vehicle into the backcountry. My understanding of the backcountry is that it’s pretty completely closed off, outside of horse and foot access.
Glacier is awesome though. I know they have tons of vehicle access campsites, they just aren’t in the backcountry. Gorgeous scenery, perfect weather. It’s worth spending time in glacier even if all you do is drive the going to the sun road.
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