2 weeks road trip
 

I am planning a two week road trip. After reading some posts I realized that 2 weeks are not enough for a cross country drive, so I am looking for some loops suggestions. I am traveling with a 16 years old son with autism. The reason I am mentioning this is because he easily gets tired from big cities and a lot of activities, but he loves nature, history, small towns. Could you please recommend an itinerary? Ps Would love to include the Yellow Stones.

It would help if you told us where you are starting from. That way contributors here can help plan a route that includes Yellowstone.

^^^ ditto

Where are you traveling from? Also, when is the trip (season can make a big difference) ? If you live somewhere in the west, a loop drive could easily be worked out that would include Yellowstone. But if you are in the eastern part of the US then most likely you'd have to fly out to somewhere in the west/northwest and start your loop there.

So give us more details to work with.

^^^ ditto
Following janisj 's suggestion if you or he do not like to fly, the Amtrak California Zephyr from Chicago or any mid-west station to Salt Lake City would be a good choice. You travel on the train overnight through a lot of what some people consider "fly over country". The westbound train leaves Omaha Nebraska about 11PM and you are in Denver at breakfast time (when on time). Even if the train is late, remember you are on a vacation and you don't have to be in SLC early to get the rental car. The 50 mile stretch east of Glenwood Springs Colorado is one of the most beautiful daytime areas on the Zephyr route.
Yellowstone is an easy days drive from SLC. Spend a few days there and then decide between Mt. Rushmore, Glacier NP or maybe Craters of the Moon in Idaho. Return the car in Salt Lake City and see the city for a few hours before the return trip on the east bound Zephyr (late night or early morning). If you wanted another day or two on the trip you could get off in Glenwood Springs. Glenwood Springs has the world's largest hot spring fed swimming pool, a gondola ride up to a cavern and a great hiking/bike trail into the canyon. The other notable thing I saw in GWS was the hike up to the cemetery where I saw the monument to Doc Holliday. He is not buried under it. He is buried somewhere in the cemetery but no one living knows where.