Law and legislation 137 National parks and reserves 104 Historic sites 92 Wilderness areas 35 Outdoor recreation 32 Parks 32 Public lands 31 History 26 National monuments 26 Recreation areas 22 Recreation 20 Antiquities 19 Indians of North America 16 Archaeology 13 Indigenous peoples 13 Buildings 11 Trails 11 Appropriations and expenditures 10 Monuments 10 Roads 10 Excavations (Archaeology) 9 Federal aid to outdoor recreation 9 Recreational use 9 Wild and scenic rivers 8 Administrative agencies 7 Gifts 7 Historic preservation 7 Planning 7 Boxing 6 Civil war 6