The Côte d'Azur (French pronunciation: ; literal translation "Coast of Azure"), often known in English as the French Riviera, is the Mediterranean coastline of the southeast corner of France, also including the state of Monaco. There is no official boundary, but it is usually considered to extend from the Italian border (Italian Riviera) in the east to Saint-Tropez, Hyères, Toulon, or Cassis in the west. This coastline was one of the first modern resort areas. It began as a winter health resort for the British upper class at the end of the 18th century. With the arrival of the railway in the mid-19th century, it became the playground and vacation spot of British, Russian, and other aristocrats, such as Queen Victoria and King Edward VII, when he was Prince of Wales. In the summer, it also played home to many members of the Rothschild family. In the first half of the 20th century, it was frequented by artists and writers, including Pablo Picasso, Henri Matisse, Edith Wharton, Somerset Maugham, and Aldous Huxley, as well as wealthy Americans and Europeans. After World War II, it became a popular tourist destination and convention site. Many celebrities, such as Elton John and Brigitte Bardot, have homes in the region. Officially, the Côte d'Azur is home to 163 nationalities with 83,962 foreign residents, although estimates of the number of non-French nationals living in the area are often much higher. Its largest city is Nice, which has a population of 347,060 (2006). The city is the center of a communauté urbaine – Nice-Côte d'Azur – bringing together 24 communes and more than 500,000 inhabitants and 933,080 in the urban area. Nice is home to Nice Côte d'Azur Airport, France's third-busiest airport (after Paris-Charles de Gaulle Airport and Paris-Orly), which is on an area of partially reclaimed coastal land at the western end of the Promenade des Anglais. A second airport at Mandelieu was once the region's commercial airport, but is now mainly used by private and business aircraft. The A8 autoroute runs through the region, as does the old main road generally known as the Route nationale 7 (officially now the DN7 in the Var and the D6007 in the Alpes-Maritimes). Trains serve the coastal region and inland to Grasse, with the TGV Sud Est service reaching Nice-Ville station in five and a half hours from Paris. The French Riviera has a total population of more than two million. It contains the seaside resorts of Cap-d'Ail, Beaulieu-sur-Mer, Saint-Jean-Cap-Ferrat, Villefranche-sur-Mer, Antibes, Juan-les-Pins, Cannes, Saint-Raphaël, Fréjus, Sainte Maxime and Saint-Tropez, It is also home to a high-tech/science park or technopole at Sophia-Antipolis (north of Antibes), and a research and technology center at the University of Nice Sophia-Antipolis. The region has 35,000 students, of whom 25 percent are working toward a doctorate. The French Riviera is a major yachting and cruising area with several marinas along its coast. According to the Côte d'Azur Economic Development Agency, each year the Riviera hosts 50 percent of the world's superyacht fleet, with 90 percent of all superyachts visiting the region's coast at least once in their lifetime. As a tourist center, French Riviera benefits from 310 to 330 days of sunshine per year, 115 kilometres (71 miles) of coastline and beaches, 18 golf courses, 14 ski resorts and 3,000 restaurants.