Acadia National Park (Maine)
Visited 2004
Arches National Park (Utah)
Visited 2001, 2002, 2003, 2004, 2005, 2008, 2012, 2013, and 2018
Badlands National Park (South Dakota)
Visited 2003
Big Bend National Park (Texas)
Visited 2004
Biscayne National Park
Visited 2021
Black Canyon of the Gunnison National Park (Colorado)
Visited 2002 and 2004
Bryce Canyon National Park (Utah)
Visited 2001, 2003, 2004, 2006, 2012, and 2017
Canyonlands National Park (Utah)
Visited 2001, 2002, 2004, 2005, 2008, 2012, and 2018
Capitol Reef National Park (Utah)
Visited 2001, 2003, 2004, 2005, 2006, 2008, 2009, and 2010
Carlsbad Caverns National Park (New Mexico)
Visited 2003 and 2004
Channel Islands National Park (California)
Visited 2009
Congaree National Park (South Carolina)
Visited 2011
Crater Lake National Park (Oregon)
Visited 2006
Cuyahoga Valley National Park (Ohio)
Visited 2012
Death Valley National Park (California, Nevada)
Visited 2003, 2009, 2011, 2012, 2013, and 2015
Dry Tortugas National Park (Florida)
Visited 2021
Everglades National Park (Florida)
Visited 1993 and 2021
Gateway Arch National Park (Missouri)
Visited 2004
Glacier National Park (Montana)
Visited 2005 and 2021
Glacier Bay National Park (Alaska)
Visited 2024
Grand Canyon National Park (Arizona)
1986, 2002, 2005, 2009, and 2011
Grand Teton National Park (Wyoming)
Visited 2001, 2003, 2004, and 2020
Great Basin National Park (Nevada)
Visited 2003, 2007, and 2022
Great Sand Dunes National Park (Colorado)
Visited 2014
Great Smoky Mountains National Park (Tennessee, North Carolina)
Visited 2011
Guadalupe Mountains National Park (Texas)
Visited 2003 and 2004
Haleakalā National Park (Hawaii)
Visited 2003
Hawaii Volcanoes National Park (Hawaii)
Visited 2010
Hot Springs National Park (Arkansas)
Visited 2004
Indiana Dunes National Park (Indiana)
Visited 2013
Isle Royale National Park (Michigan)
Visited 2018
Joshua Tree National Park (California)
Visited 2002, 2010, and 2013
Kenai Fjords National Park (Alaska)
Visited 2024
Kings Canyon National Park (California)
Visited 2002 and 2017
Lassen Volcanic National Park (California)
Visited 1992, 2004, and 2006
Mammoth Cave National Park (Kentucky)
Visited 2004 and 2006
Mesa Verde National Park (Colorado)
Visited 2001 and 2010
Mount Rainier National Park (Washington)
Visited 2007
North Cascades National Park (Washington)
Visited 2019
Olympic National Park (Washington)
Visited 2007
Petrified Forest National Park (Arizona)
Visited 2004
Pinnacles National Park (California)
Visited 2014
Point Pelee National Park (Ontario, Canada)
Visited 2015
Redwood National Park (California)
Visited 2006
Rocky Mountain National Park (Colorado)
Visited 2001 and 2005
Saguaro National Park (Arizona)
Visited 2009
Sequoia National Park (California)
Visited 2002 and 2017
Shenandoah National Park (Virginia)
Visited 2003
Theodore Roosevelt National Park (North Dakota)
Visited 2018
Voyageurs National Park (Minnesota)
Visited 2018
Waterton Lakes National Park (Alberta, Canada)
Visited 2005
White Sands National Park (New Mexico)
Visited 2004
Wind Cave National Park (South Dakota)
Visited 2003 and 2005
Yellowstone National Park (Wyoming, Montana, Idaho)
Visited 2001, 2002, 2003, 2007, and 2020
Yosemite National Park (California)
Visited 1986, 2004, 2005, and 2017
Zion National Park (Utah)
Visited 1986, 2002, 2003, 2004, 2005, 2007, 2011, 2012, and 2017
Not visited in USA: (1) American Samoa (American Samoa); (2) Denali (Alaska); (3) Gates of the Arctic (Alaska); (4) Glacier Bay (Alaska); (5) Katmai (Alaska); (6) Kenai Fjords (Alaska); (7) Kobuk Valley (Alaska); (8) Lake Clark (Alaska); (9) New River Gorge (West Virginia); (10) Virgin Islands (U.S. Virgin Islands); (11) Wrangell-St. Elias (Alaska)