We took the train one year with the kids from Socal to ND to see the grandparents and got off at West Glacier to stay overnight, rented a car to drive around, drive over and back.
Its really something you should do once at least if you want to visit the magnificent Cathedrals of the American West national parks.
Iirc there is a size limit on RVs and towed trailers on some sections
www.nps.gov
And reservations go fast on campgrounds, but check just outside the park if you cant get a spot inside.
Someone here was going soon and might be up to comment if pinged...
@gregangsten
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