Illinois-Indiana State Line Boundary Marker (Chicago, Illinois)

 memorial, monument, landmark, historical marker, interesting place, boundary marker

Illinois State Line Marker (Hammond, Indiana)

1822 · believed to be the oldest historical monument in Chicagoland — a tall, plain, but harmonious limestone structure with multiple fossils (crinoids?) weathering out on its surface, located where the northwest corner of Indiana touches the eastern border of Illinois. To state that this is the intersection of State Line Road and 103rd Street is correct, except that both streets are interrupted near this point by industrial and railroad developments. The visitor must approach from the north to find the monument in the small Allen J. Benson Park at the entrance to the Commonwealth Edison State Line generating plant. Bronze plaques explain that the "State Line was retraced by Act of Congress 1833" and that the marker is now located 191.09 feet north of its original site, and 159.359 miles due north from the Wabash River.