Subject
Frontier and pioneer life
376
West (U.S.) Description and travel
375
West (U.S.) History
362
West (U.S.)
257
Indians of North America
125
Geology
102
Overland journeys to the Pacific
102
Water-supply
75
Geology, Stratigraphic
70
West (U.S.) Discovery and exploration
64
Indians of North America Wars
62
Cowboys
56
Paleontology
53
West (U.S.) Social life and customs
52
History
48
Water rights
46
West (U.S.) In literature
45
Public lands
44
Water resources development
42
Public lands Management
41
United States Discovery and exploration
39
Crime
37
Fur trade
37
Uranium ores
37
Outlaws
36
Mines and mineral resources
35
Pioneers
33
Cattle trade
32
Trails
32
Military life
28
Rocky Mountains
26
United States Territorial expansion
26
Wilderness areas
26
American literature History and criticism
24
Forest management
24
Ranch life
24
United States History
24
Explorers
23
Indians of North America History
22
Petroleum
22
California Description and travel
21
Geology, Structural
21
Water quality management
21
Climatic changes
20
Environmental policy
20
Indians of North America Claims
20
Oregon National Historic Trail
20
West (U.S.) Economic conditions
20
Range management
19
Travel
19
more ...