Paris for 31 percent of the GDP of France. According to the Economist Intelligence Unit Worldwide Cost of Living Survey in 2018, Paris was the second-most expensive city in the world, behind Singapore and ahead of Zurich, Hong Kong, Oslo and Geneva. The city is a major rail, highway, and air-transport hub served by two international airports: Paris-Charles de Gaulle (the second busiest airport in Europe after London Heathrow Airport with 69.5 million passengers in 2017) and Paris-Orly. Opened in 1900, the city's subway system, the Paris Métro, serves 5.23 million passengers daily, and is the second busiest metro system in
Mihail Kogălniceanu International Airport Airport opened for civil operations in May 1960, when it replaced the old Palas Airport (founded in 1932). A passenger terminal with a capacity of 200 passengers per hour was inaugurated in 1962, followed, five years later, by an expansion to a processing capacity of 300 pax/hour. In 1974, a major expansion increased the processing capacity to 1,000 pax/hour. Use of the airport peaked at 778,766 passengers in 1979, when foreign tourism to the Romanian Riviera was at a high. Mihail Kogălniceanu International Airport handled 127,635 passengers in 2017, which represents a 34.9% increase over the previous year. The airport