Region
Montana
Custer County
9
Rosebud County
6
Carbon County
2
Chouteau County (Mont.)
1
Custer County (Mont.)
1
Fort Union Formation
1
Liberty County (Mont.)
1
Pondera County (Mont.)
1
Powder River Basin (Wyo. and Mont.)
1
Snider Creek Region
1
Terry Region
1
Teton County (Mont.)
1
Toole County (Mont.)
1
Upper Missouri National Wild and Scenic River (Mont.)
1
Upper Missouri River Breaks National Monument
1
Upper Missouri River Breaks National Monument (Mont.)
1
Valley County
1
Yellowstone River
1