Paris addresses usually refer to the numbered district, or arrondissement (1-20). You’ll see these shaded on the map; they spiral out from the center. Most things you’ll want to see will be in 1 through 8. Best places for wandering are near the river, in the 1st, 4th, and 6th. The 5th is considered the student neighborhood, so more comic book and game stores, arty movie theaters, bookstores, etc. The 8th is more high end, with the Golden Triangle of fashion between Avenue George V and Avenue Montaigne as well as the twin foodie heavens of Fauchon and Hediard on the Place de la Madeleine.
Don’t let snooty Parisians get to you—the French as a whole are not so bad. Remember that the best way to get service is to be humble and make sure that, the moment you enter a store, you greet the employee with Bonjour Monsieur or Bonjour Madame—this gets you further than you’d think. Or, if you really need help or a favor, Polly Platt’s “five magic words” (Excusez-moi de vous déranger…) are essential to begin any request.
Subway Travel: The metro is very easy in Paris and within the city limits you are never far from an entrance. Remember to look for the stop at the end of the line in the direction you want to go—this is how the subway platforms are marked. Important: You often need your used ticket to exit so don’t toss it until you have completely exited the system. They also do random ticket checks on the subway and you must be able to produce it.
Subway Tickets: What you buy depends on how much you think you’ll need the subway. Paris is very walkable, living there I almost never got a monthly pass because I walked so many places. The streets are not too crowded and there is almost always something cool to see along the way. If you want to cram in a lot, however, the subway could save you lots of time.
Option 1: Individual trip tickets. If you go this route, I would suggest you buy packets of ten (called carnets [car-nay]) as you need them. Carnets are much cheaper (14.1€) than individual tickets (1.8€ x 10). After a day, you should be able to gauge how many you need and not have too many left over. Note: If you go to Versailles, or outside Paris on the RER, you will need a special zoned ticket.
Option 2: Unlimited tickets. Avoid the tourist rip-off, which is the “Paris-Visite” card. If you want an unlimited ticket for the day, buy a “Mobilis” ticket for Zones 1-2 (7€) or, if you’re going to Versailles that day, Zones 1-4 (11.50€).
Museum, Movie, and other Tickets: You can buy a “Carte Musées et Monuments” (Paris Museum Pass) at any subway booth, but it cost 42€ for two days and 56€ for 4 days, so it is probably not worth it, unless you plan on visiting a lot of museums (or a lot on one day). But the pass does allow you to cut lines. If you want to know what’s playing in theaters and cinemas, or about museum exhibits and monument hours, buy a Pariscope or L’Officiel des Spectacles at the nearest kiosk. These weekly magazines come out every Wednesday and are your best, cheap guide for anything you want to visit.
Sightseeing (beyond the obvious):
Try to walk around at night: Paris lights up its monuments and walking around, especially by the river, is really beautiful. Try the Pont des Arts (a pedestrian bridge) near the Louvre and head into the small courtyard in the Louvre opposite the end of the bridge (the Cour Carrée). Apparently, the new thing is to put locks with initials and messages on the bridge. This area is pretty and calm at night. Also go around to the other side and check out the Louvre pyramids lit up. By the way, have no fear walking around the city center at night. I used to cross the river at all hours heading home by myself. But do watch for pickpockets, especially on the subway or crowded tourist areas.
Best views of the city: Most people head for the Eiffel Tower or the Arc de Triomphe but I’d suggest either climbing the tower of Notre Dame (cool gargoyles and very central so the view is more interesting) or the slightly lower altitude but free option of the top floor of the Centre Pompidou, also called Beaubourg. Just ride the escalators past the public library to the café at the top and check out the balcony view. The plaza around the Pompidou museum is also very cool with wild Niki de St-Phalle fountain sculptures and various street performers.
Best ride: You might want to take a bateau mouche. There are lots of different companies that run these 1-hour (usually) boat tours on the Seine—they’re touristy but they give great views of most of the major monuments, especially pretty at night. You can also take the Batobus, which is cheaper and makes all the key stops, where you can get on and off and back on again. There’s no tourist commentary, but that might be a good thing.
Favorite shadow: Bizarre but true, I have a favorite shadow. If you are on the Pont d’Arcole next to the Hotel de Ville (City Hall, very pretty at night too) look for the great shadow cast by the statue of the man on horseback—very cool. If you take a bateau mouche boat at night you’ll also see it.
Favorite neighborhood: I love the area around the St. Sulpice church, which has a great fountain and a good café, the Café de la Mairie, for people watching. There are fabulous stores around as well as the Jardin de Luxembourg, a nice park. Of course, I’m biased, as this is my old neighborhood from when I used to teach at Sciences-Po and had an adorable teeny tiny studio on the equally teeny tiny rue du Sabot.
This spot is also close to the St.-Germain cafés, which should be tried at least once. My favorite is La Palette at 43 rue de Seine, although the Bar du Marché down the street at 75 rue de Seine is also good, especially for people watching at the market on the rue du Buci. Among the big two, Café de Flore and Deux Magots, next door to each other on the bd St-Germain, my preference is for Flore, which always seemed less touristy. I actually did run into Karl Lagerfeld out front one day.
Best museums: If you like medieval tapestries, try Cluny, in the 5th arrondissement next to the Sorbonne. If you like Picasso, people find that museum very good. Plus, it’s in the Marais, the funky, gay, formerly Jewish neighborhood, good for exploring. If you’re in the Marais, check out the Place des Vosges nearby, a very pretty square. My favorite museum spot is the park of the Rodin Museum, near Invalides (Napoleon’s tomb and the military museum). At the Rodin museum, you can just visit the garden since most of his main sculptures are displayed outside, or pay full fare to check out smaller works, and “The Kiss,” inside. Many locals go there for lunch, or to sit outside.
Best spooky/morbid places: Definitely the catacombs in the 14th. The entrance is located right near the metro stop Denfert-Rochereau. This is a series of underground tunnels filled with bones. Very Edgar Allen Poe and not for the claustrophobic.
Runner up in morbidity are the cemeteries, the tombs are really beautiful and interesting. Montparnasse and Montmartre are good but the best is Père Lachaise in the north-east area of the city (also a good place for a picnic—I kid you not), where Jim Morrison, the medieval lovers Héloïse and Abelard, and Oscar Wilde are buried, among others.
Best chateaux: Versailles is an obvious choice, and incredible. If you go, try to go for the day and really see the outlying gardens and parks. IIRC you can rent bikes pretty cheaply for riding around the park. Another good choice would be Fontainebleau—Henri II’s (and later Napoléon’s) great chateau south of the city, a bit more intimate and less clogged with tourists. The Fontainebleau forest is also a great place for walking and riding, more wild than Versailles.
Best ticket in town: An opera or ballet at the Palais Garnier. Although the acoustics are better at the Opéra Bastille, you can’t beat the original on the Avenue de l’Opéra. Even the boxes in the cheap seats are incredible.
Favorite tea shop: Mariage Frères. I used to buy my tea at the shop hidden away on the rue des Grands Augustins in the 6th, and still go there to stock up when in town, but to actually have tea I would probably go to the location in the 4th, at 35 Rue Bourg Tibourg. Old standby blends I always stock up on are Casablanca (a green/black blend of mint/Earl Grey), Chandernagor (chai), and Rose d’Himalaya (darjeeling). My new favorite flavor that my cousin brought me recently is Swan Lake, a green tea with roses and violets.
Foie gras and other foodstuffs: G. Detou at 58 rue Tiquetonne. If only I had known about this when my friend Scott used to live on the fun-to-say rue Tiquetonne! My cousin’s foodie husband turned me on to this out-of-the-way treasure for all things épicerie. If you are in the neighborhood, be sure to check out St. Eustache, an enormous church in Les Halles, with almost no visitors—a welcome relief after the hugely crowded Notre-Dame.
Favorite clothing store for kids: Du Pareil au même (DPAM). There are branches around the city, but I’m partial to the one on the bd St.-Germain since it’s such a great shopping neighborhood in general. If you have little kids in your life, this is a great store for cute, good quality clothes at reasonable prices.
[ETA: The prices listed in this post were updated in September 2015.]