Driving distance from Alexandria, VA to Manassas, VA. The total driving distance from Alexandria, VA to Manassas, VA is 36 miles or 58 kilometers. Your trip begins in Alexandria, Virginia. It ends in Manassas, Virginia. If you are planning a road trip, you might also want to calculate the total driving time from Alexandria, VA to Manassas, VA so you can see when you'll arrive at your destination.