• Protected areas of Illinois by county‎ (93 C)

A

• Abraham Lincoln National Heritage Area‎ (18 P)
• Arboreta in Illinois‎ (9 P)

B

• Bike paths in Illinois‎ (2 C, 5 P)

F

• Forests of Illinois‎ (2 C, 12 P)

H

• Hiking trails in Illinois‎ (2 C, 11 P)

I

• Illinois State Historic Sites‎ (57 P)

N

• National Forests of Illinois‎ (2 C)
• National Park Service areas in Illinois‎ (2 C, 2 P)
• National Wildlife Refuges in Illinois‎ (13 P)
• Nature centers in Illinois‎ (21 P)
• Nature reserves in Illinois‎ (4 C, 38 P)

P

• Parks in Illinois‎ (6 C, 35 P)

R

• Reservoirs in Illinois‎ (60 P)

S

• Illinois state forests‎ (6 P)

W

• Wilderness areas of Illinois‎ (8 P)

Σ

• Illinois protected area stubs‎ (74 P)