Just got a 31 foot travel trailer in Nov. and am planning on taking the family out to the Black Hills and Yellowstone this summer. I was wondering if anybody could share their experiences about the campgrounds, where you stayed etc. Are they crowded, what are the facilities like, is it hard to get in and out of certain places? Also any sites we shouldn't miss. Haven't been out that way since childhood so it will be like the first time. Thanks!