A long layover at John F. Kennedy International Airport (JFK) offers several distinct experiences depending on your time frame. If you have 4-6 hours, the TWA Hotel in Terminal 5 is a must-visit; it is a mid-century modern masterpiece featuring a rooftop infinity pool overlooking the runway and a cocktail lounge inside a converted 1958 Lockheed Constellation airplane. For layovers longer than 8 hours, you can take the AirTrain to Jamaica Station and transfer to the Long Island Rail Road (LIRR), which puts you in Penn Station, Manhattan in about 35 minutes. This gives you enough time to see Times Square, grab a New York slice, or walk the High Line before heading back. If you prefer to stay on-site, Terminal 4 offers premium lounges and high-end shopping. For those needing rest, "Minute Suites" provide private nap rooms. Just remember to factor in at least 2 hours for security re-entry and AirTrain transit, as JFK is massive and transit times between terminals can be unpredictable during peak New York traffic hours.