Glacier National Park is all about the alpine lakes and the sheer scale of the mountains. You want to go in late summer when the high-country trails are finally clear of snow and the water is that impossible shade of turquoise. It is a massive place, so expect to spend a lot of time behind the wheel on Going-to-the-Sun Road.
A trip like this usually runs about $1800 for the basics. You can manage that cost over time using the Discover it® Cash Back (Discover), which offers 0% intro APR for 15 months on purchases and balance transfers. This gives you a 15-month window to pay off the trip without paying extra in interest.
Remember that the 0% intro APR is a deadline, not a gift. If you still have a balance on the card once those 15 months are up, the bank will start charging you interest on what is left over.