Yellowstone allows private, licensed outfitters who have been authorized to operate in the park to guide trips. Some outfitters offer day trips and some offer guided overnight backcountry trips. Yellowstone National Park Lodges also offers one to two hours horse rides at Tower-Roosevelt and Canyon. Private Trips. People may bring private stock into the park. Planning and preparation are the keys to a successful trip. Whether you are taking a day ride or camping overnight, you must follow all stock packing regulations, which include carrying proof of a negative Coggins Test for each of your animals.