Saint Martin (French: Saint-Martin; Dutch: Sint Maarten) is an island in the northeast Caribbean, approximately 300 km (190 mi) east of Puerto Rico. The 87-square-kilometre (34 sq mi) island is divided roughly 60/40 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 Collectivité de Saint-Martin (Collectivity of St. Martin) and is an overseas collectivity of France.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.