Frankfurt am Main Airport (IATA: FRA, ICAO: EDDF), known in German as Flughafen Frankfurt am Main or Rhein-Main-Flughafen is an international airport located in Frankfurt am Main, Germany, 12 km (7 mi) southwest of the city centre. Run by Fraport, it is by far the busiest airport by passenger traffic in Germany, the third busiest in Europe and the ninth busiest worldwide in 2008. It serves the most international destinations in the world and is the busiest airport in Europe by cargo traffic. The southern side of the airport, Rhein-Main Air Base, was a major airlift base for the United States from 1947 until late 2005, when it was acquired by Fraport. The airport is directly located in the Frankfurt Rhine Main Region, Germany's second largest metropolitan area, which itself has a central location in the densely populated region of west-central Europe. Thereby, along with a strong rail and motorway connection, the airport serves as a major transportation hub to the greater region, less than two hours by ground to Cologne, the Ruhr Area, and Stuttgart. There are plans to expand Frankfurt Airport with a fourth runway and a new Terminal 3. First modifications to the airport to make it Airbus A380 compatible are completed, including the first building of a large A380 maintenance facility near the former U.S. Air Base. The work on the fourth runway has been delayed several times due to environmental concerns, but received zoning approval in December 2007. The runway could be in operation by 2010. Frankfurt is a hub of Lufthansa, the German national carrier. Lufthansa's secondary hub is Munich Airport where many key medium and long haul routes are available, lessening the need to overburden Frankfurt Airport. Frankfurt Airport has two terminals. Terminal 1 is divided into concourses A, B and C. Terminal 2 is divided into concourses D and E. Frankfurt Airport has 45 boarding gates altogether. A general aviation Terminal (GAT) is located south of the main runway system.