Over 38,000 pounds of limestone marks a spot of great importance. It is the Illinois-Indiana State Line Boundary Marker. This obelisk stands as a testament to the establishment of the border between Illinois and Indiana.
Let’s step back to 1838. The Office of the United States Surveyor General erected this marker. It replaced a simple pine post from 1821. The Illinois-Indiana State Line Boundary Marker sits near the northernmost point between the two states. Today, it straddles the line between Hammond and Chicago. It is near the end of Avenue G on Chicago’s East Side. It is also just west of where the State Line Generating Plant used to be.
The Illinois-Indiana State Line Boundary Marker is more than just a pile of rocks. It is a historical artifact. The obelisk stands over 15 and a half feet tall. It marks a line 159.359 miles north of where the straight-line border meets the Wabash River. The Wabash River forms the rest of the border between Illinois and Indiana.
Originally, the Illinois-Indiana State Line Boundary Marker was closer to Lake Michigan. It stood 191.09 feet south of its current spot. Over time, landfill from industrial development pushed the shoreline north. By the 1980s, the obelisk was hidden and vandalized.
In 1988, local conservationists stepped in. They moved the Illinois-Indiana State Line Boundary Marker to a safer location. It was placed next to the guard house for the State Line Generating Plant.
The generating plant closed in 2012. It was torn down soon after. This left the Illinois-Indiana State Line Boundary Marker’s future uncertain again. In 2021, Hammond and Chicago joined forces. They created State Line Plaza. This small park ensures the marker remains accessible.
Did you know this marker is one of Chicago’s oldest structures? Only the Noble-Seymour-Crippen House built in 1833 and the Henry B. Clarke House built in 1836 are older. Chicago recognized its importance on September 4, 2002. The Illinois-Indiana State Line Boundary Marker was awarded Chicago Landmark status.
Consider what this marker represents. It is more than a line on a map. It symbolizes the history and collaboration between two states. The Illinois-Indiana State Line Boundary Marker is a reminder of how borders are created, shifted, and preserved. As we stand here, we are straddling not just a line but also a shared past and a connected future.