Orly Airport, located in the southern suburbs of Paris, replaced Le Bourget as the principal airport of Paris from the 1950s to the 1980s. Charles de Gaulle Airport, located on the edge of the northern suburbs of Paris, opened to commercial traffic in 1974 and became the busiest Parisian airport in 1993. Today it is the 4th busiest airport in the world by international traffic, and is the hub for the nation's flag carrier Air France.  Beauvais-Tillé Airport, located 69 km (43 mi) north of Paris' city centre, is used by charter airlines and low-cost carriers such as Ryanair.