Caribe Hilton San Juan
Not many hotels can boast about having their own fort, but Fortín San Gerónimo del Boquerón, which once guarded the entrance to San Juan Bay, is on the grounds of this 17-acre sprawling resort. It has a private beach, a multilevel pool with a swim-up bar, and a luxurious spa. The airy and iconic Oasis lobby bar makes one of the more legitimate claims to having invented the piña colada; it holds an official government certification.