In 1962, the Ohio Department of Highways implemented the system of Interstate Highways that had been approved by the states in 1956.
The State Route numbers 70, 71, 74, 75, 77, 80, 90, 270, 271, 275, 277, 280, 290, 675, and 680 conflicted with new designations, so the State Routes with those numbers were renumbered.
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