I think Yellowstone and the Tetons are quite hard to wrap your arms around until you visit, not that you shouldn't research, but it will be easier to plan your second trip... which, no doubt you will want to make after your first visit. I am now plan...
I spent several days at Madison last year and then moved down for several days at GTNP. I would suggest splitting it between parks at the very least. I would consider splitting your time between the east and west sides or north and south sides if you...
