According to the California Protected Areas Database (CPAD), in the state of California, United States, there are over 14,000 inventoried protected areas administered by public agencies and non-profits. In addition, there are private conservation areas and other easements. They include almost one-third of California's scenic coastline, including coastal wetlands, estuaries, beaches, and dune systems. The California State Parks system alone has 270 units and covers 1.3 million acres (5,300 km2), with over 280 miles (450 km) of coastline, 625 miles (1,006 km) of lake and river frontage, nearly 18,000 campsites, and 3,000 miles (5,000 km) of hiking, biking, and equestrian trails.