Counties in Illinois

• Adams (27 historic properties)
• Alexander (7 historic properties)
• Bond (2 historic properties)
• Boone (4 historic properties)
• Brown (2 historic properties)
• Bureau (13 historic properties)
• Calhoun (6 historic properties)
• Carroll (6 historic properties)
• Cass (2 historic properties)
• Champaign (56 historic properties)
• Christian (5 historic properties)
• Clark (8 historic properties)
• Clay (5 historic properties)
• Clinton (2 historic properties)
• Coles (20 historic properties)
• Cook (511 historic properties)
• Crawford (7 historic properties)
• Cumberland (3 historic properties)
• De Kalb (14 historic properties)
• De Witt (2 historic properties)
• Douglas (2 historic properties)
• Du Page (39 historic properties)
• Edgar (8 historic properties)
• Effingham (2 historic properties)
• Fayette (4 historic properties)
• Ford (5 historic properties)
• Franklin (3 historic properties)
• Fulton (43 historic properties)
• Gallatin (7 historic properties)
• Greene (13 historic properties)
• Grundy (7 historic properties)
• Hamilton (4 historic properties)
• Hancock (9 historic properties)
• Hardin (5 historic properties)
• Henderson (4 historic properties)
• Henry (16 historic properties)
• Iroquois (5 historic properties)
• Jackson (15 historic properties)
• Jasper (1 historic property)
• Jefferson (2 historic properties)
• Jersey (18 historic properties)
• Jo Daviess (17 historic properties)
• Johnson (2 historic properties)
• Kane (68 historic properties)
• Kankakee (13 historic properties)
• Kendall (9 historic properties)
• Knox (7 historic properties)
• La Salle (29 historic properties)
• Lake (90 historic properties)
• Lawrence (1 historic property)
• Lee (9 historic properties)

• Livingston (13 historic properties)
• Logan (12 historic properties)
• Macon (10 historic properties)
• Macoupin (8 historic properties)
• Madison (38 historic properties)
• Marion (6 historic properties)
• Marshall (1 historic property)
• Mason (4 historic properties)
• Massac (3 historic properties)
• McDonough (6 historic properties)
• McHenry (12 historic properties)
• McLean (31 historic properties)
• Menard (6 historic properties)
• Mercer (10 historic properties)
• Monroe (6 historic properties)
• Montgomery (13 historic properties)
• Morgan (9 historic properties)
• Moultrie (1 historic property)
• Ogle (23 historic properties)
• Peoria (29 historic properties)
• Perry (2 historic properties)
• Piatt (5 historic properties)
• Pike (12 historic properties)
• Pope (2 historic properties)
• Pulaski (4 historic properties)
• Putnam (4 historic properties)
• Randolph (15 historic properties)
• Richland (4 historic properties)
• Rock Island (24 historic properties)
• Saline (4 historic properties)
• Sangamon (61 historic properties)
• Schuyler (2 historic properties)
• Scott (2 historic properties)
• Shelby (6 historic properties)
• St. Clair (20 historic properties)
• Stark (1 historic property)
• Stephenson (16 historic properties)
• Tazewell (15 historic properties)
• Union (5 historic properties)
• Vermilion (12 historic properties)
• Wabash (1 historic property)
• Warren (10 historic properties)
• Washington (3 historic properties)
• Wayne (2 historic properties)
• White (10 historic properties)
• Whiteside (11 historic properties)
• Will (34 historic properties)
• Williamson (4 historic properties)
• Winnebago (30 historic properties)
• Woodford (8 historic properties)