One of United Airlines ORD Terminal main hubs, Terminal 1 at Chicago O'Hare International Airport (ORD), is where the airline primarily operates. The majority of the departure gates, TSA security checkpoints, and United's checkin counters are located in Concourses B and C of Terminal 1. Among the facilities available to United passengers are the United Club lounges in both concourses, with the Polaris Lounge in Concourse C catering to business class passengers from abroad. There are several places to eat and shop, including Tortas Frontera, a local favorite. United may also use Terminal 5, which is reachable by the airport's transit system, for some international flights.