Columbia subject headings:
National parks and reserves--United States--History.
Public lands--United States--History.
Wilderness areas--United States--History.
Harvard subject headings:
National parks and reserves--United States--History
Public lands--United States--History.
Wilderness areas--United States--History.
Princeton subject headings:
National parks and reserves--United States--History.
Public lands--United States--History.
Wilderness areas--United States--History.