Hank MI wrote:
Can't see you doing Yellowstone and the Grand Canyon in one trip. Unless you want to drive non-stop and not see anything. You're looking a days of driving just to get to one or the other then the same to return. Now if you plan on driving around the clock to get there well maybe.
I probably don't drive as many miles a day as you will but last summer we drove from MI to the Black Hills. Then to Yellowstone and back home. A little over 3 weeks and we could have used more time. We saw a lot but there were things we didn't see. Honestly, as everyone else said, pick one or the other. There's enough to see and do and you won't have to spend the whole time driving. Try to cram in too much and it's no longer a vacation. It becomes a chore, rushing from one place to the other with no time to enjoy any of it.
X2 on the above.
You will be driving constantly. With only two weeks to visit BOTH places, your options to see anything are going to be very limited. Drive a lot and not stop to see hardly anything on the way out and back. Once you get to Yellowstone, you'll only have enough time to drive to the major attractions and spend little time at each one (Yellowstone is a HUGE place). Then drive to Grand Canyon and peek over the edge and then head for home.
People can suggest lots of great places for your family to visit, but you won't have time to really see or experience any of them if you keep to your 2-destination and 2 week schedule. How are those 2 teenagers and 2 tweeners going to feel sitting in the RV constantly? My suggestion: Pick only one destination and then enjoy it and those things in the immediate vicinity. For sheer variety, I would suggest Yellowstone, because then you can also hit Black Hills on the way there, Cody, Grand Tetons and Jackson (if you are an active family, lots of activities the teenagers may like around Jackson).