Region
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North Carolina
3
Oklahoma
1
Oregon Caves National Monument (Or.)
1
Orlando
1
Pennsylvania Avenue (Washington, D.C.)
1
Pontchartrain, Lake, Watershed
1
Potomac River
1
President's Park (Washington, D.C.)
1
Prince George's County
1
Prince George's County (Md.)
3
Rock Creek (Md. and Washington, D.C.)
1
Rock Creek Park (Washington, D.C.)
6
Rock Creek Park Public Golf Course (Washington, D.C.)
1
Rock Creek and Potomac Parkway (Washington, D.C.)
1
Russia
2
Saint Lawrence Island
1
Saint Louis
1
San Antonio
1
South Dakota
1
Southeast Federal Center (Washington, D.C.)
1
Southwest Waterfront (Washington, D.C.)
1
Spring Valley (Washington, D.C.)
2
Swain County
1
Swain County (N.C.)
1
Texas
3
Ukraine
1
United States
204
Utah
1
Vancouver
1
Vermont
1
Virginia
8
Washington (D.C.)
Washington (State)
1
Washington Channel (Washington, D.C.)
1
Washington Metropolitan Area
3
Washington Region
1
West Potomac Park (Washington, D.C.)
1
White House Gardens (Washington, D.C.)
2