More than 25.6 million travelers pass through the Salt Lake City International Airport (SLC) each year. The airport, which is located four miles west of downtown, has four runways and three passenger terminals with five concourses and 44 gates. Alaska Airlines, American Airlines, Delta Air Lines, Frontier Airlines, JetBlue Airways, Southwest Airlines, and United Airlines all operate from SLC. Delta, which has the largest market share at SLC, also uses the airport as a hub. Airport services include a number of restaurants and retails stores. There are also ATMs, charging stations, a currency exchange, free WIFI internet and shoe-shine stands. Ground transportation options include rental cars, taxis and shuttles, as well as TRAX light rail and bus service.