Subject
- Boundaries20
- Administrative and political divisions10
- Counties7
- Environment5
- Society4
- States4
- Conservation easements3
- Open spaces3
- Planning and Cadastral3
- Protected areas3
- Public lands--Fees3
- Wilderness areas3
- Biology and Ecology2
- Elementary schools2
- Inland Waters2
- School districts2
- Wilderness area monitoring2
- Battlefields1
- Farming1
- Forest reserves1