The Alfredo Jahn Cave Natural Monument (Monumento Natural Cueva Alfredo Jahn) is located four kilometers to the west of the town of Birongo, Miranda State, in the eastern sector of the Serranía Littoral (coastal mountains) of the Cordillera de la Costa (coastal range). With a network of passages measuring 4.29 kilometers (2.67 miles), it is the largest cave in the central region of Venezuela, as well as one of the most visited in the country. The humid cave, which is still active, has been formed by the action of Cambural Creek. Its calcite walls are covered with spectacular stalagmites, stalactites, and columns that are best developed in the Salón del Chaguaramo (Palm Chamber) or the Salón de la Lluvia (Rain Chamber).
A seasonal, semi-deciduous, premontane forest surrounds the cave, which contains three strata of dense thickets. Among the most common tree species are the araguaney (Tabebuia chrysanta) and the gumbo-limbo (Bursera simaruba). Frequent flooding of the creek has limited the establishment of troglobyte fauna (animals living exclusively in the cave); however, an abundant fauna of insects and arachnids exists, as well as populations of four important species of bats, including large numbers of vampire bats (Desmodus rotundus rotundus).
There are two small villages established within the natural monument, but the agricultural areas located in the Cambural Creek watershed are the main threat. Because this watershed feeds the hydrologic system of the cave, these agricultural areas pose a problem to the integrity of the geologic processes at work there. For this reason, this protected area is classified as threatened.