The airport is for most holidaymakers the least enjoyable part of your break.
Long queues, eye-stinging bright lights, heating turned up to melting point and ludicrously expensive food - and that's providing your flight runs on time.
But there's another potential headache if your boarding pass is stamped with 'SSSS' alongside the regular information such as your name and flight number.
Before you notice the code you will have probably been unable to print it from one the automatic printing machines; instead you'll have to get it printed at the check-in desk.
And this is where the 'fun' starts.
SSSS stands for 'Secondary Security Screening Selection', an abbreviation used by the Transportation Security Administration (TSA), which means you've been selected for an interrogation.
While there's no official explanation for why you're selected, according to Life Hacker , there are a few reasons which may have contributed.
Frustratingly, it's sometimes randomised. But last-minute flights could be one reason, as could taking an international one-way fare.
If you've paid for that flight in cash, that may also mean you now qualify, as can travelling from somewhere which is classified as a "high-risk country."
And if you're on a watch list, you can definitely expect this to appear on your pass.
What happens next?
One thing to bear in mind is, if you have not been able to print your pass off, you may want to arrive at the airport even earlier than planned.
This is because if this code appears, as long as up 30 minutes could be added to your getting through security.
First you'll be taken to your own security line where you’ll go through every security screening possible, including going through a metal detector and body scanner twice, and getting a full body pat-down.
Then security painstakingly go through your carry-on bags, with each item getting wiped down for explosive residue.
Eventually a form will be filled out and your boarding pass will be stamped and you'll finally be allowed on your flight.
Probably in need of a holiday more than ever.
This story appeared in The Mirror.