Coiba

Declared in 1991 and a UNESCO World Heritage Site since 2005, Coiba owes its exceptional state of preservation, paradoxically, to having served as a Panamanian penal colony between 1919 and 2004: the general dread of escaping onto a remote island and its reputation for harshness kept settlers and poachers away for decades, unintentionally preserving the largest island in the American Pacific all but untouched. Since the prison finally closed in 2004, its waters — home to one of the healthiest shark populations in the region — have become one of the most highly regarded dive destinations in Central America.