Rio Abajo Forest is a forested preserve in Puerto Rico owned by the Department of Natural Resources. It was designated a National Natural Landmark in 1980 and constitutes an area of 3,590 acres.
The reserve was established in 1935 by Puerto Rico’s Reconstruction Administration. The massive reserve is situated between the Dos Bocas Lake and the Tanamá River and this lends itself to the unusual topography of the region. It is quite common to find caves, sinkholes and small hills within close proximity to each other in the reserve. The hills are largely made of limestone and many of them house a number of subterranean cavities that are tempting to explore. However, if you are inexperienced this is not recommended unless you are accompanied by a guide who can keep you safe and prevent you from getting lost. One popular option is that of taking a guided tour of the underground rivers that flow through the region. If you prefer to concentrate on what is above the ground instead of what is underneath it, you will find that the Rio Abajo Forest Reserve is home to more than 200 plant species and as many as 175 different species of wildlife.
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