Polly and Bill Cunningham are lifelong hikers and wilderness advocates. They have collaborated on several other FalconGuides, including Wild Utah, Hiking New Mexico's Gila Wilderness, Hiking New Mexico's Aldo Leopold Wilderness, Best Easy Day Hikes Joshua Tree, Hiking California's Desert Parks, Hiking Mojave National Preserve, Hiking Joshua Tree National Park, Hiking Death Valley National Park, and Hiking Anza-Borrego Desert National Park. Bruce Grubbs is an avid camper, backpacker, hiker, mountain biker, and cross-country skier who has been exploring the American desert for over thirty years. A professional outdoor writer and photographer, he has written many previous FalconGuides, including Hiking Arizona. He lives in Flagstaff, Arizona.