73 books • 9 series
Book #1: Bryce Canyon and Zion National Parks: Danger in the Narrows
Book #1: Bryce and Zion: Danger in the Narrows
Book #2: Grand Canyon: Tail of the Scorpion
Book #2: Grand Canyon National Park: Tail of the Scorpion
Book #3: Yosemite National Park: Harrowing Ascent of Half Dome
