The year Puerto Rico's capital San Juan was founded, making it the second-oldest European settlement in the Americas (after Santo Domingo in the Dominican Republic). Old San Juan has an array of colonial buildings to explore. Stay at the Gran Hotel El Convento, which dates back to 1651. Doubles from $238 (£160) elconvento.com
The size, in acres, of "El Radar", the largest radio telescope in the world. It's set in a vast sinkhole among the limestone formations near Puerto Rico's north coast. The peculiar geology of the area also gives rise to the vast cave system which can be explored in the nearby Parque de las Cavernas del Rio Camuy. naic.edu; welcome.topuertorico.org /city/camuy.shtml
The age of Hunter S Thompson when he wrote The Rum Diary, a story about a journalist living in San Juan. The book is now being made into a film starring Johnny Depp. To sample some Caribbean spirit for yourself, try the Bacardi Rum factory near San Juan, known as the "Cathedral of Rum". casabacardi.org
The area, in square miles, of Puerto Rico. It is home to a variety of landscapes a mountainous interior and lush rainforest. El Yunque National Forest boasts excellent walking trails. Casa Cubuy is set within the park, with views of the jungle. Doubles from $120 (£80), with breakfast. casacubuy.com
The distance in miles between Puerto Rico and the tiny island of Culebra, to the east of the mainland.
Self-catering apartments overlooking Flamenco beach start at $146.25 (£97) per night for two, from Culebra Beach Villas. culebrabeachrental.com
The depth, in feet, of the Puerto Rico Trench, the deepest point in the Atlantic Ocean, 75 miles north of Puerto Rico. To scuba dive in the waters which surround the island, Dive Puerto Rico offers a two-tank morning dive from $119 (£79) at Fajardo and Palmas del Mar on the east coast. divepuertorico.com
The number of years that Puerto Rico has been an "Estado Libre Asociado" (a free associated state) of the United States, following the adoption of a new constitution on 25 July 1952, which followed years spent as a Spanish colony, and later under American occupation. The head of state is still the US President. For more information , see gotopuertorico.com
The price, in pounds, per person for the new 14-night Puerto Rico stay-and-cruise offered by Virgin Holidays Cruises this winter (based on two sharing). The itinerary includes seven nights on the island, plus a seven-night trip aboard the Caribbean Princess to islands including Dominica, Grenada, Tortola, Antigua, St Lucia and Barbados (the specific stops vary with departure date). Virgin Atlantic flights from Gatwick are included in the price; the first departure is on 7 November.