Region
United States Virgin Islands
3
Alaska
1
Arizona
1
Buck Island Reef National Monument
1
California
1
Chesapeake and Ohio Canal National Historical Park
1
Colorado
1
Colorado Plateau Region
1
Elwha River Watershed
1
Katmai, Mount (Alaska)
1
Lassen Volcanic National Park
1
Organ Pipe Cactus National Monument
1
Potomac River Valley
1
Saint John
1
Salt River Bay National Historical Park and Ecological Preserve
1
Salt River Bay National Historical Park and Ecological Preserve (United States Virgin Islands)
1
Washington (D.C.)
1
Washington (State)
1
Yellowstone National Park
1