This 444-acre forest, located just west of Manassas National Battlefield on Route 29, has five miles of trails running through a mixture of pine plantation, and mixed pine and old-growth hardwoods stands.
Trail map. Recommended 3.5-mile hiking route: walk the length of the yellow trail and turn right on the blue trail. In a short distance, turn left on the orange trail. At it's low point, it gives you a glimpse of Little Bull Run. The orange trail returns to the blue trail. Go left on the blue trail, and take the first right on the unmarked black trail, which returns you to the yellow trail. Turn left on the yellow trail, go a short distance and turn left on the old railroad bed, following it as far as you can. It becomes the blue trail, which eventually turns right and winds its way back to the beginning of the yellow trail and the parking lot.
The park includes an area of pine plantations that are maintained with selective cutting, tree-plantings, and prescribed burns. Only tall shelterwood pines—the strongest, healthiest trees—are left standing to provide seeds for new trees, and shade that protects young seedlings from the elements. During the Depression, the Civilian Conservation Corp (CCC) planted “Penny Pines,” which were loblolly pines bought by the public as a war-relief fundraiser during World War Two. Foresters now manage these trees as “old growth” loblolly to preserve their historical significance.
You can walk on an old railroad grade (see photo below), built between 1854 and 1858, that crosses the park between the yellow and pink trails. The planned 35-mile railroad line started in Alexandria, ran through the City of Fairfax to Chantilly, crossed Bull Run at Sudley Springs, then headed southwest across what is now the Manassas Battlefield National Park and Conway Robinson State Forest, to join the Manassas Gap Railroad in Gainesville, which extended west from Manassas to the Shenandoah Valley.
Because of mounting costs for purchasing land and moving earth for the track bed, as well as social and economic turbulence during the years leading-up to the Civil War, work stopped on the rail line one year before it was completed. The steel rails were staged in Alexandria, but none were ever laid on the track bed. It's remarkable that stone was quarried for bridge abutments and all the cuts and fills were done by hand, mostly by local laborers, many of which were slaves and Irish immigrants. Some of the cuts and embankments were used for cover and movements by Confederate and Union troops during pitched Civil War battles. You can tour these battle sites on the "Unfinished Railroad Loop Trail" in the Manassas Battlefield National Park. The rail bed was abandoned after the Civil War.