Every autumn, a quarter million people go to Virginia’s famed Shenandoah National Park to see the spectacular fall colors of the Blue Ridge Mountains. Those traveling along Skyline Drive, the park’s main road, pass a routered wood sign pointing to Lewis Mountain. Eighty years ago, the park marker included an additional line: “Negro Area.” It indicated the way to the only purpose-built segregated camping area in the southern national parks. Today, the Shenandoah Valley Black Heritage Project is working to preserve the memory of this easily overlooked piece of park…