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Never. They are very busy on holidays.
Airports are always open just may not have people on staff depending on the size of the airport.
Some small ones are put on automatic control to turn on the lights at night. Just key the radio and activate the lights.
No. Certainly not the major ones. I suppose it's possible that some private airfields will close for the holiday, though.
no, i flew to my mother's funeral on the 4th one yr, theyre open
No, not for landings and takeoffs (runway use).
Smaller airports may not have services available on holidays though (fuel, food, etc.).
