Travelers are flocking to airport lounges in search of complimentary food, drinks and perhaps most importantly, a chance to relax away from the hordes of travelers at the gate. Delta's new Sky Club at New York's John F. Kennedy International Airport Benji Stawski / CNBCDelta Air Lines Sky Club lounges — and the credit cards that grant entry to them — became so popular that customers complained about the long lines and crowds at many locations. More spaceDelta, United Airlines and American Airlines are racing to build more lounges and spaces and larger ones to fit high demand. The carrier separately operates a network of Polaris lounges for travelers booked in its highest cabin class, usually on long-haul international routes. United Airlines Polaris lounge at Newark Liberty International Airport.

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Persons: John F, Benji Stawski, —, Delta, Allison Ausband, Leslie Josephs Organizations: Sky Club, New, Kennedy International, CNBC Delta Air Lines Sky, —, CNBC, John, Delta, United Airlines, American Airlines, Denver International Airport, Polaris, United Airlines Polaris, Newark Liberty International Airport Locations: U.S, New York, Delta