When was the route that U.S. Route 123 is a spur of originally made?
U.S. Route 123: U.S. Route 123 (US 123) is a spur of US 23 in the U.S. states of Georgia and South Carolina. U.S. Route 23:  It is an original 1926 route which originally reached only as far south as Portsmouth, Ohio, and has since been extended.
1926