Saint Martin (French: Saint-Martin; Dutch: Sint Maarten) is an island in the northeast Caribbean, approximately 300 km east of Puerto Rico. The 87 km2 island is divided roughly 60/40 between France (53 km2) and the Kingdom of the Netherlands (34 km2); they are roughly equal in population. It is one of the smallest sea islands divided between two nations, a division dating 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.
...and here's a view from Maho Bay, a plane landing at Princess Juliana airport, which serves the Dutch part of the island of Saint Martin. In 2007, the airport handled 1,647,824 passengers and 103,650 aircraft movements. The airport serves as a hub for Windward Islands Airways and is the major gateway for the smaller Leeward Islands, including Anguilla, Saba, St. Barthélemy and St. Eustatius. It is named after Juliana of the Netherlands, who as crown princess landed here in 1944, the year after the airport opened. There is also an airport on the French side of the island, called Aéroport de Grand Case or L'Espérance Airport. The airport is perhaps best known for very low-altitude flyover landing approaches due to one end of its runway being extremely close to the shore and Maho Beach.
This is the stamp on the second postcard, sadly not cancelled, but still mailed from Saint Martin. :)