 The original eastern terminus was likely at Springfield Avenue in Newark, which was at the time Route 24.When that highway was truncated to the Maplewood/Irvington line, the segment of Route 24 east of South Orange Avenue was made part of CR 510; the route extended east of Route 21 along Market Street and Raymond Boulevard to an eastern terminus at the intersection of U.S. Route 1/9 and U.S. Route 1/9 Truck on the very eastern edge of Newark.This routing definitely existed in 1973, though the exact start and end dates are uncertain.