Adolfo Suárez Madrid–Barajas Airport ( ) is the main international airport serving Madrid in Spain. In 2015, almost 47 million passengers used Madrid–Barajas, making it the country's largest and busiest airport, and Europe's sixth busiest. It opened in 1928, and has grown to be one of the most important aviation centres of Europe. Located within the city limits of Madrid, it is just from the city's financial district and northeast of the Puerta del Sol, Madrid's historic centre. The airport name derives from the adjacent district of Barajas, which has its own metro station on the same rail line serving the airport. Barajas serves as the gateway to the Iberian peninsula from the rest of Europe and the world, and is a particularly key link between Europe and Latin America. The airport is the primary hub and maintenance base for Iberia. Consequently, Iberia is responsible for more than 60 percent of Barajas' traffic.