The 87-square-kilometre (34 sq mi) island is divided roughly 61/39 between France (53 km2, 20 sq mi) and the Kingdom of the Netherlands (34 km2, 13 sq mi); the two parts are roughly equal in population. It is the smallest inhabited sea island divided between two nations. The division dates to 1648. The southern Dutch part comprises Sint Maarten and is one of four constituent countries that form the Kingdom of the Netherlands. The northern French part comprises the CollectivitÃ© de Saint-Martin (Collectivity of St. Martin) and is an overseas collectivity of France.
St. Martin's Dutch side is known for its festive nightlife, beaches, jewelry, drinks made with native rum-based guavaberry liquors, and casinos. The island's French side is known for its nude beaches, clothes, shopping (including outdoor markets), and French and Indian Caribbean cuisine. English is the most commonly spoken language along with a local dialect. The official languages are French for Saint-Martin, and both Dutch and English for Sint Maarten. Other common languages include various French-based creoles (spoken by immigrants from other French Caribbean islands), Spanish (spoken by immigrants from the Dominican Republic and various South American countries), and Papiamento (spoken by immigrants from Aruba, Bonaire and Curacao).
Tourists often use accommodations such as hotels, guesthouses, villas, and timeshares.
Rental cars are the primary mode of transportation for visitors staying on island. Traffic on the island has become a major problem. Long traffic jams between Marigot, Philipsburg and the airport are common.
Because the island is located along the intertropical convergence zone, it is occasionally menaced by tropical storm activity in the late summer and early fall.
Neighboring islands include Saint Barthelemy (French), Anguilla (British), Saba (Dutch), Sint Eustatius "Statia" (Dutch), Saint Kitts and Nevis (independent, formerly British). With the exception of Nevis, all of these islands are easily visible on a clear day from St. Martin.
On January 1, 2009, the population of the entire island was 77,741 inhabitants, with 40,917 living on the Dutch side, and 36,824 on the French side.
Collectively, the two territories are known as "St-Martin / St Maarten". Sometimes SXM, the IATA identifier for Princess Juliana International Airport (the island's main airport), is used to refer to the island.
Under the Koppen climate classification, the island has a tropical monsoon climate with a dry season from January to April and a rainy season from August to December. The precipitation patterns are due to the movement of the Azores high during the year. With the wind direction predominantly from the east or the northeast, temperatures remain stable throughout the year and temperatures rarely exceed 34 C (93 F) or fall below 20 C (68 F). Temperatures remain steady throughout the year with an average mean temperature of 27.2 C (81.0 F). The average sea temperature is 27.2 C (81.0 F) ranging from a low of 25.9 C (78.6 F) in February to a high of 28.4 C (83.1 F) in October. The total average yearly rainfall is 1,047 mm (41.2 in), with 142 days of measurable rainfall. Thunderstorms can occasionally occur, with 18 days with thunder per year.