Elenco (na ordem dos créditos)
David Michael Gee
Narrator(voice)
Terry Baldino
Park Ranger at Death Valley National Park
Dave Bengston
Director at the Yosemite Mountaineering School
Vickie Carson
Public Information Officer at Mammoth Cave National Park
Lincoln Else
Park Ranger at Yosemite National Park
Dan Engstrom
Operations Supervisor at Amtrak
Andy Fisher
District Park Ranger at Grand Teton National Park
Kris Fisher
Public Affairs Officer at Denali National Park
Mike Gauthier
Head Climbing and Rescue Ranger at Mt. Rainier National Park
John Gray
Owner of Glacier Wilderness Guides
Chris Groves
Professor of Geography at Western Kentucky University
Hank Heasler
Geologist at Yellowstone National Park
Mark Hyde
Self
Shauna Hyde
Wayne Johnson
River Guide at Grand Teton National Park
Ron Kaye
Park Ranger at Zion National Park
Anthony Linforth
Park Ranger at Acadia National Park
Cindy Micheli
Park Ranger at Capitol Reef National Park
Riley Mitchell
Chief of Interpretation at Capitol Reef National Park
Patricia Owen
Wildlife Biologist at Denali National Park
Gregg Pohll
Park Ranger at Crater Lake National Park
Ann Rockefeller Roberts
Author
Jackie Skaggs
Public Affairs Officer at Grand Teton National Park
Douglas Smith
Wildlife Biologist at Yellowstone National Park
Benita Tsao
Park Volunteer at Crater Lake National Park)
Peter Whittaker
Mountain Guide at Rainier Mountaineering Inc.
Ed Winterberg
Carriage Manager at Acadia National Park