In the United States, legacy airlines operate hub-and-spoke networks, funneling passengers through centralized hubs to connect them between any two cities in their network with relative ease. In Europe, most legacy carriers will have a single major hub, through which almost every single one of their flights will pass. Examples of such hub facilities include British Airways’ principal hub at London Heathrow Airport (LHR) and Air France’s primary gateway at Paris Charles de Gaulle Airport (CDG).