Also known as Lindbergh Field, San Diego International Airport (SAN) is located three miles northwest of downtown. The airport, which is a focus city for Southwest Airlines, is the busiest single-runway commercial airport in the United States. In 2014, about 18.8 million travelers passed through the airport. About 20 carriers operate at SAN, with non-stop flights offered to about 60 destinations in the United States, Canada, Mexico, England and Japan. San Diego International Airport has three passenger terminals (Terminal 1, Terminal 2 and the Commuter Terminal) with a total of 55 gates. Passenger services and amenities at SAN include restaurants, retail stores, several lounges, a spa, a USO lounge, a free cell phone waiting lot, art exhibits, ATMs, currency exchanges and shoeshine stands.