Virginia State Route 309

State Route 309 (SR 309) is a primary state highway in the U.S. state of Virginia. Known for most of its length as Old Dominion Drive, which was once the right of way of the Great Falls Division of the Washington and Old Dominion Railroad, the state highway runs 5.33 miles (8.58 km) from SR 123 in McLean east to U.S. Route 29 (US 29) in Arlington.