Yellowstone National Park is mostly in Wyoming, with some of the park in Montana and Idaho. Hike to learn about the trails, springs, geysers, and wildlife in this national park. Megan Cooley Peterson is a children's book author and editor. Her book How To Build Hair-Raising Haunted Houses (Capstone Press, 2011) was selected as a Book of Note by the TriState Young Adult Review Committee. When not writing, Megan enjoys movies, books, and all things Halloween. She lives in Minnesota with her husband and daughter.