Río Encantado Protected Natural Area

The Río Encantado Protected Natural Area (735.79 ha / 1,818.18 cuerdas) protects a portion of the larger Río Encantado Karst Interest Area (~6,448 ha / 16,000 acres), a vast, road-less karst region in Puerto Rico's northern limestone belt — the second-largest tract of contiguous forest on the island after El Yunque. The area hosts the Río Encantado Underground River and Cave System, one of the world's longest continually traversable underground rivers (~17 km / 10.5 miles) and Puerto Rico's longest cave system. Its landscape features sinkholes, mogotes (haystack hills), alluvial valleys, and deep limestone gorges. 547 species have been documented in the area (403 plants, 42 birds — including 12 endemics, more than two-thirds of Puerto Rico's endemic bird species —, 16 mammals, 8 reptiles, 5 amphibians, and 73 invertebrates), among them the Puerto Rican Boa (Epicrates inornatus), federally listed as endangered. Puerto Rico's northern karst belt has been identified as one of the ten most endangered karst ecosystems in the world. The area is managed by the Conservation Trust of Puerto Rico, which began acquiring land here in 2000; due to its rugged terrain and lack of roads, public access is very limited and there are no developed public trails.