Situated largely on the Caribbean Plate, the region comprises more than 7,000 islands, islets, reefs, and cays. These islands, called the West Indies, generally form island arcs that delineate the eastern and northern edges of the Caribbean Sea. These islands are called the West Indies because when Christopher Columbus landed there in 1492 he believed that he had reached to the west of the Indian sub-continent.
The region consists of the Antilles, divided into the larger Greater Antilles which bound the sea on the north, the Lesser Antilles on the south and east (including the Leeward Antilles), the Bahamas, and the Turks and Caicos Islands or the Lucayan Archipelago, which are in fact in the Atlantic Ocean north of Cuba, not in the Caribbean Sea.
Geopolitically, the West Indies are usually regarded as a subregion of North America and are organized into 30 territories including sovereign states, overseas departments, and dependencies. From January 3, 1958, to May 31, 1962, there was a short-lived country called the Federation of the West Indies composed of ten English-speaking Caribbean territories, all of which were then UK dependencies. The West Indies cricket team continues to represent many of those nations.