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
Frankfurt Airport regional station Frankfurt Airport regional station Frankfurt (Main) Airport regional station () is an underground railway station at Frankfurt Airport in Frankfurt, Germany. It provides local S-Bahn and "Regionalbahn" services to the city and the Frankfurt/Rhine-Main Metropolitan Region. The station opened on 14 March 1972 together with a new passenger terminal (Terminal Mitte, now called Terminal 1). At the time it was only the second railway station serving an airport in Germany (after Berlin Schönefeld Airport Station). In 1999, a second train station opened at Frankfurt Airport (Frankfurt Airport long-distance station) which is primarily used by long-distance trains, mostly ICE services. Prior