 Most of SR 234 southeast of Manassas, for 15.85 miles (25.51 km) from State Route 28 in Manassas towards State Route 31 (U.S. Route 1) at Dumfries, was added to the state highway system in 1928 as State Route 709.The final 2.50 miles (4.02 km) were added in 1929, making SR 709 a continuous Manassas-Dumfries route.In the other direction, from Manassas northwest towards Gilberts Corner, 6.42 miles (10.33 km) were added in 1930 and 1931.