On Tuesday my wife and I are traveling to Billings, Montana to begin our 3 week trek through Montana, Wyoming, South Dakota and Utah. Going to lots of National Parks and Monuments. We are very excited to experience everything. If anyone likes, please share your experiences and any suggestions you may have for us. We have prepared a jammed pack itinerary. Thanks.
Went to Montana and Yellowstone NP last Sept. We were on a m/c trip.
1. Considering the elevation, it is cold in the morning (even colder when riding a M/C). However, by 11 AM, it started getting warm, and stayed that way past dinner time. So, if you are outside the car a lot, wear layers that you can take off and put on.
2. Speaking of weather, it's not uncommon for a storm to happen quickly through the mountains. Carry some emergency gear with you. If you are renting a car (and it appears you are), ask the rental agency if they have emergency kits, or you can purchase one through Amazon/local auto supply store. They are roughly $50. Carry extra water and snacks.
3. Yellowstone is amazing. See Old Faithful. Be mindful of the wild animals. DO NOT THINK THEY ARE TAME, and don't be the one that ends up on TV for getting attacked by a large wild animal.
4. Every 10 feet is another photo op.
5. We came in from Missoula (so, west of Yellowstone). There are some natural hot springs in that area that are worth a stop.
6. Since you are "travelling through Montana", I will assume you are also heading west of Billings. Try the "Going to the Sun" road. It takes you to Glacer NP. We did not do it, but heard it is amazing.