These two green islands, set in the turquoise sea some 27 km (16 miles) north of the mainland, have more than a dozen white-sand beaches, twice that many coral reefs, and mangrove shallows that attract great flocks of flamingos. The more secluded Cayo Santa María usually gets grouped in with Coco and Guillermo, too; development has been slower to come to Santa María than to its bigger neighbors, but that situation is not expected to last. Ernest Hemingway made frequent fishing trips to these keys and described them in Islands in the Stream. Long uninhabited and visited only by local fishermen and the occasional millionaire, the islands now have several modern beach resorts, with even more under construction. They have become Cuba's third most popular tourist destination, following Havana and Varadero.
A causeway traverses the shallow Bahía de Perros (Bay of Dogs) south of Cayo Coco; from this key, shorter causeways stretch west to Cayo Guillermo and east to the undeveloped Cayo Romano. All three islands are covered with a thick scrub vegetation; mangrove swamps line their southern shores; and bleached-sand beaches scallop their northern edges. The fishing is good; in addition to the marlin that so fascinated Papa, there are wahoo, tuna, mahimahi, and sailfish. Sportfishing charters are available out of the marinas on both keys; you can arrange them at any hotel. The diving (particularly off Cayo Guillermo) is even better than the angling, with dozens of healthy coral reefs inhabited by hundreds of fish species—from the delicate butterfly fish to the menacing barracuda—as well as a dizzying array of invertebrates. Visibility averages 20 to 35 meters (66 to 115 feet).