Region
United States
65
Canada
15
France
12
Congo (Democratic Republic)
4
Luxembourg
4
Morocco
4
Senegal
4
Côte d'Ivoire
3
Gabon
3
Mali
3
Bandiagara Caves (Mali)
2
Belgium
2
Benin
2
Comoros
2
Mexico
2
Niger River Valley
2
North Pacific Region
2
Outer space
2
Algeria
1
Burkina Faso
1
Cameroon
1
Chad
1
Czech Republic
1
Djibouti
1
Finland
1
Great Britain
1
Great Lakes (North America)
1
Great Lakes Watershed (North America)
1
Guinea
1
Hungary
1
Madagascar
1
Monaco
1
Niger
1
North Atlantic Region
1
North Dakota
1
North Macedonia
1
Poland
1
Saint Lawrence Seaway
1
Saskatchewan
1
Souris River Watershed
1
Sweden
1
Togo
1