Fray Jorge National Park, national park in the Coquimbo región, north-central Chile. It lies about 60 miles (100 km) directly south of La Serena on the Pacific coast. Established in 1941 and covering 38 square miles (100 square km), it preserves a pocket of subtropical forest in a semiarid region. Botanists conjecture that this unusual situation exists because the relatively warm discharge of nearby Limarí River into the cold Pacific Ocean creates an almost continuous fog, providing moisture for the forest. The park was designated a UNESCO World Network Biosphere Reserve in 1977.