You’ve just bought a ten-pack of Paris Metro tickets (a carnet) and none of them work! When you try to go through the turnstile, the red light flashes. Have you put your metro tickets in a pocket that also has keys, spare change or a USB memory stick? Any of these items may de-magnetize your Metro tickets. The solution is easy. Just go to the Metro ticket booth, hand in your Metro ticket in exchange for one that works. This will be a problem in some of the Metro stations that are unmanned however, so don’t get caught and keep your Metro tickets separate from change and keys.
>> There are more Paris travel tips from a local to help you plan the best Paris trip, too!