Karen Berger has hiked thousands of miles of trails in the national parks of the United States. She is the author of 20 books, including America’s Great Hiking Trails and America’s National Historic Trails.

Jonathan Irish has photographed on all seven continents and in more than 80 countries. For the 2016 National Park Service Centennial, Irish went on assignment to photograph all of America’s national parks.

Sally Jewell served as U.S. secretary of the interior from 2013 to 2017, overseeing the nation’s national parks, wildlife refuges, and public lands under President Barack Obama.

With more than 1.6 million members and supporters, National Park Conservation Association is the voice of America’s national parks, working to protect and preserve the nation’s most iconic and inspirational places for present and future generations. It celebrates the parks—and works tirelessly to defend them—whether on the ground, in the courtroom, or on Capitol Hill. From its national headquarters in Washington, DC, and 27 regional offices, it calls on its program and policy experts, committed volunteers, staff lobbyists, community organizers, and communications specialists to ensure that national parks are well protected.