Campbell Hill is, at 1,549.09 feet, the highest point in elevation in the U.S. state of Ohio. Campbell Hill is located within the city of Bellefontaine, 2 miles northeast of downtown. The peak is the former home of the Bellefontaine Air Force Station, where the 664th Aircraft Control and Warning Squadron maintained a Cold War early warning radar. Curreā¦Campbell Hill is, at 1,549.09 feet, the highest point in elevation in the U.S. state of Ohio. Campbell Hill is located within the city of Bellefontaine, 2 miles northeast of downtown. The peak is the former home of the Bellefontaine Air Force Station, where the 664th Aircraft Control and Warning Squadron maintained a Cold War early warning radar. Currently, the summit is occupied by the Ohio Hi-Point Career Center and is open to visitors Monday through Friday.