Caja de Muertos Island
Seen from certain points along Puerto Rico's southern coast, the island gives the impression of a dead person lying on a plateau. That, at least, is the official explanation for the name Caja de Muertos - Dead Man's Chest - attributed to the 18th-century French writer Jean-Baptiste Labat, who called it Coffre à mort. But official explanations only go so far on an island that has been called Isla Abeiranas, Isla Bestia, Isla del Tesoro, and a dozen other names since the Taíno people first paddled out to its shores. Uninhabited today, protected as a nature reserve, Caja de Muertos sits eight miles off the coast of Ponce, a two-mile sliver of dry forest, limestone, and five beaches whose turquoise waters hide coral reefs and the nesting grounds of endangered sea turtles.
Pirates, Treasure, and a Copper Coffin
The stories that cling to Caja de Muertos read like drafts of a novel that was never quite finished. In 1599, a group of English merchants-turned-pirates seized a Portuguese ship loaded with gold, silver, and precious stones off the Indian coast. Fleeing toward England, they survived a mutiny and took refuge on the island. When some of the crew ventured to the Puerto Rico mainland for provisions, Spanish authorities killed all but one, who confessed to the hidden treasure. The colonial governor appropriated what remained. Then there is the tale of José Almeida, a Portuguese pirate who buried his wife in a glass-and-copper coffin in a cave on a deserted island near Ponce after she was killed by a stray bullet on their first raid together. He returned monthly to gaze at her preserved body and leave half his plunder at her grave, until he was caught and executed at Castillo San Felipe del Morro in 1832. Whether these stories explain the island's name is uncertain. That they shaped its character is not.
Revolutionaries in the Scrub
Caja de Muertos attracted more than pirates. During the 19th century, the island served as a secret refuge for Puerto Rican patriots who opposed Spanish rule. Ramón Emeterio Betances and Segundo Ruiz Belvis, two of the most prominent figures in the independence movement, are documented among those who used the island as a hideout. Freemasons, persecuted on the mainland, held clandestine meetings in its isolation. By 1898, when the American invasion began, the island had a permanent population of 64 residents who survived without fresh water - collecting rainfall when they could and importing water from the mainland when rain failed. A decade later, only 16 remained. The Spanish government had constructed a lighthouse between 1880 and 1887, and when automation made its keepers unnecessary, the last reason to live on Caja de Muertos vanished. The population dropped to zero, and the island became what it remains: a place people visit but do not stay.
Turtles and Dry Forest
The Caja de Muertos Nature Reserve protects the island and its surrounding waters primarily because of its sea turtle nesting habitat. The dry forest that covers the island's interior is ecologically valuable in its own right, supporting species found nowhere else. The island measures two miles long and averages about a third of a mile wide, with an area of 0.59 square miles. Morrillito Key lies 591 feet off the southwest point, and Berbería Key sits 3.9 miles to the northeast, both part of the reserve. The climate is arid, and the vegetation is scrubby - cacti, drought-adapted shrubs, and the low trees characteristic of Caribbean dry forest. The lighthouse, established in 1887 and automated in 1945, still functions atop the island's highest hill, 170 feet above the sea. Five beaches ring the coast: Playa Pelícano, which earned Blue Flag certification in 2010, Playa Ensenadita, Playa Larga, Playa Blanca, and Playa Chica. Pelícano faces the mainland and draws the most visitors; Larga faces the open Caribbean and is protected from public access.
Fragile Paradise
Reaching Caja de Muertos requires a catamaran from the La Guancha Boardwalk in Ponce, a trip that was interrupted twice in recent years. Hurricane Maria in 2017 badly damaged La Guancha, and the 2020 Puerto Rico earthquakes damaged it again. After the earthquakes, the reserve's infrastructure deteriorated sharply. The DRNA ranger housing was severely damaged and went unrepaired for over a year, leaving the island without on-site protection. By 2021, the last of three patrol vehicles broke down, and maritime rounds stopped entirely. Without enforcement, some visitors breached protected areas, anchored boats in the sand, rode jet skis through turtle habitat, camped illegally, and vandalized structures. The Department of Natural and Environmental Resources has built a dock, barracks, trail signs, and composting bathrooms, and the government has repeatedly announced restoration priorities. But the tension between accessibility and protection defines Caja de Muertos today. The island's beauty is real, its ecology fragile, and its future dependent on whether the commitment to preserve it matches the legends that make people want to visit.
From the Air
Located at 17.89°N, 66.52°W, approximately 8 miles south of Ponce off Puerto Rico's southern coast. The island is clearly visible from altitude as a distinct elongated landmass oriented northeast-southwest, roughly 2 miles long. The lighthouse on the 170-foot hill at the southwest end is a useful visual reference. Nearby keys Morrillito (southwest) and Berbería (northeast) are also visible. Nearest airport is Mercedita Airport (TJPS/PSE) in Ponce, approximately 10 nm north. The island sits in generally clear, dry air on Puerto Rico's south coast with good visibility. Turquoise shallow waters around the island contrast with deeper blue Caribbean. Coral reefs are visible as darker patches in clear conditions. Ferry route from La Guancha Boardwalk in Ponce is often visible as a wake line.