I was fortunate enough to go on the "Great American Road trip" this year. I was quite nervous crossing the US that I would not find many types of food that I could eat, especially in the more rural areas (e.g. a yurt on the Wyoming and Montana border). With careful planning, I was able to maintain a stable diet, that incorporated fresh, wholesome foods.
For the car ride, for snacking I packed:
Overall, my best advice if you are planning on taking a road trip, no matter how long it is, would be to pack a variety of foods that you enjoy eating. It would be beneficial if these foods also do not make you thirsty, are wholesome and filling, are not empty carbs that will lead to blood sugar spikes and excessive eating. Eat small amounts often, and have the food easily accessible and organized.
Remember to eat- sometimes if you are out on an excursion for the day it can be so overwhelming that you forget to eat. You will, or at least I get tired and cranky when I don't eat, so plan around meal and snack times.
Try your best not to eat while driving
"The release of norepinephrine inhibits the release of neurotransmitters that might cause you to feel relaxed or aid in the digestion of food. This is one reason eating while driving is bad for you—when your stress response is engaged, the ‘rest and digest’ neurotransmitters are put on hold, and so is the food in your stomach.” - Why Isn't my Brain Working by Dr Datis Kharrasian
You may have the urge to keep reaching for snacks, instead pull into a rest stop to use the bathroom, get outside and enjoy your snack. There are picnic areas with grass and picnic tables at many of the rest stops.
Yellowstone National Park was absolutely my favorite part of the road trip. I had waited my whole life to see Yellowstone, it was a lot to take in. This will certainly not be my last time to Yellowstone.