The National Park System (NPS) incorporates 85 coastal park units, including national parks, seashores, lakeshores, recreation areas, monuments, preserves, historic sites, and memorials. These areas contain over 19,000 km (12,000 mi) of shoreline, iconic American features, and a wide variety of geological, biological, and cultural resources. To protect and preserve National Park coastal resources, a clear approach to coastal sediment management based on sound coastal science and engineering is needed.