Coiba is the largest island in Central America and, until 2004, one of the most feared places in Panama: a penal colony where political prisoners were sent under the Torrijos and Noriega governments and from which few escaped, guarded as much by sharks and current as by walls. The prison is a ruin now, slowly going back to forest, and the isolation that made it a good prison is exactly what preserved it.
Because almost nobody was allowed to land for eighty years, the island and the 38 smaller ones around it kept their forest and their reefs. The national park covers more than 2,700 square kilometres and is a UNESCO World Heritage Site, and the diving is the best in the country: white-tip reef sharks in numbers, big schools of jacks and snapper, manta and mobula rays, whale sharks in season, and humpback whales passing between July and October. The endemic Coiba howler monkey and scarlet macaws survive here in a way they no longer do on the mainland.
Access is controlled. Boats run from Santa Catalina, about ninety minutes away, and you need a park permit — dive shops and operators arrange it as part of a day trip or an overnight at the ranger station, which has basic cabins and is the only place to sleep on the island.