Just thought I'd throw out some tips that I learned prior to and after my trip that proved useful to me:
A not so known rule, your passport must be good three months past the last day of your trip, so if you passport expires a week or so after your trip, you're not within this rule and should get it renewed as soon as possible.
Paris Museum Card/Pass:
Best thing ever if you plan on hitting all the sites over the course of two or three consecutive days. At most sites, in addition to gaining you entry, it will allow you to bypass the long lines at the entrances for buying tickets or getting in. Never wait in line without checking first to see whether or not your card will gain you automatic entry (it will not at Saint Chapelle and Notre Dame--you will have to wait in line). Museum Cards can be purchased through your hotel.
Opening/Closing Days and Hours
It is good to know when certain sites are closed and when the major holidays are; i.e., the Louvre, l'Orangerie and certain other national museums are closed on Tuesdays, and the Musee d'Orsay and Versailles on Mondays (fountains only run on the weekends, and even then it's not all-day long but a sporadic event), and plan your itinerary accordingly. This information is subject to change so it's best to reconfirm before your trip.
Credit Cards and ATM cards:
Give your banks and credit card companies a call before your trip and let them know what dates you will be at your destination. You'd hate to have to call them from overseas in the midst of a shopping spree wondering why your card won't work.
I loved the Lonely Planet's French phrasebook as well as the iTunes download for Rapid French by Earworms Learning which has a lot of repetition set to pleasant and mild electronica. In short, making a serious attempt and being well-mannered (saying your hellos, pleases, and thank yous) will get you far. Everyone we met was extremely helpful and gracious despite my severe butchering of the language.
Knowing how to ask for the check (l'addition) is a must; unlike in the States where your check is practically served with your meal, it is considered very rude to bring the check before you are ready.
Sortie=Exit; very helpful when exiting the metro stations
Le Menu vs. La Carte: asking for le menu would be asking for the fixed price daily specials whereas you really want to ask for la carte (the menu as we know it in the States).
Chaud and Froid: Hot and Cold. Keep this in mind when in your hotel bathroom; "C" does NOT stand for cold, but rather "chaud" which is hot. I learned this the hard way by automatically turning the "C" tap for cold.
The only thing that really enabled me to figure out the Metro was my Pocket Pilot Map of Paris which had all the stops, and most importantly, the corresponding numbers. Everyday, I'd write on a piece of paper where I needed to change trains depending on where we were going; it made it so much easier once I got to the station, and I just had to figure out which platform to stand on depending on the direction we had to go. While we purchased the packet (carnet) of ten individual tickets since it was unknown to us whether or not I could figure out how to use the Metro early on, the more economical way of doing things if you plan on using the Metro is to purchase the Carte Orange (really for the locals but supposedly can be sold to tourists with passport presentation) or
Paris Visite (meant for tourists only):
this card allows you to get around Paris over the course of 1, 2, 3, 5 days. The packets of tickets and the cards can be purchased at any major Metro station.
If you wind up purchasing individual tickets, hold onto them until you exit the system and arrive at your destination at which point you can discard them. Used tickets will be stamped on the back by the turnstile machine as you insert them.
Visit http://www.parisvisite.com/en/Carte_Parivisite_presentation.php for information and fares.
The conventional way of getting a cab in Paris is to find a taxi stand (small shelters) and wait there, not standing in the middle of the road and hailing one with your arm unless you have an early death wish. If you call for one at your hotel, be prepared to find the meter already running by the time it arrives as they charge you from wherever they are when they are called. It is cheaper to find your own or to take the Metro obviously. It is also handy to keep a copy of your hotel address with you and learn the address number in French.
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