Visit Eiffel Tower, Champ De Mars, Palais Chaillot, Pont Bir Hakeim. These are all in the west of the city and suitable for a day out. To go up the Eiffel Tower – you should get there very very early – the queues start at 8:30 even though it doesn’t open till 9am. If you are waiting in a queue it will take a long time to get both up and down the tower. After covering this area then a walk along the Seine River toward Le Grand and Petit Palais provides some nice views. If you don’t walk along the river then you can walk across to Invalides (Napoleons tomb) which is quite nice.
The Louvre, Jardin De Tuilleries, Place Vendome, Jardin Du Palais Royal – “must see” places. You can also tie this in with a trip to the Musee D’Orsee. If you like walking – you can walk up the Champs Elysee to the Arc De Triomphe it’s about 2Km.
Ile De La Cite, Il Saint Louis is the heart of Paris and where most of the picturesque opportunities lie. Saint Chapelle is famous for its stained glass – can be combined with the Concierge, last resting place of the condemned before the guillotine. You also have Notre Dame. Crossing to the left bank – it’s the south side of the river – you can visit Odeon/Mabillion, where the Parisians hang out in the evening, and if you are desperate for home coffee there is a Starbucks. Also close in this area is the Saint Sulpice, mentioned in the Da Vinci Code.
Le Marais is lively on Sundays and is also one of the oldest sections of the city. In this area there is a good selection of very good restaurants and bars. Also, the Pompidou centre, Musee Carnivalet (Paris Museum), Place De Voges.
Chinatown south of Place d’Italie in the 13th Arrondissement is lively on Sunday too & has very few tourists. The architecture is nothing special, but it is generally lively all day long.
Back side of Montmartre (north of Sacre Coeur) – is wonderful – it’s winding, steep streets set it apart from the rest of the city – it’s particularly charming.
The Quartier Latin has a lot of interesting shops and restaurants. See in particular Rue St. Andre des Arts and the streets feeding into it.
There is also a fantastic area around Rue de la Gaîté in the 14th, close to Montparnasse – the trains from Brittany arrive at Montparnasse, so the neighborhood is filled with crêpe shops, bars and people. The 5th & 6th Arrondiseements are well known, but they have a lot of charm & interesting things to see – don’t miss the Jardin de Luxembourg, a favorite of Parsiens.
Flea Market (Marche aux Puces) on the week-end – it’s something special. This is an incredible few blocks of Paris for the sheer amount of off-beat and interesting merchandise – anything you can think of, atmosphere and volume of people. A true and unique urban experience. To get there, you take metro line number 4 north to Porte de Clignancourt (last stop on the line). When you exit the metro you just walk north along the main boulevard, cross under the overpass, keep going for a few blocks and you are in it – deep.
l’Hotel des Invalides – actually – it’s a church, but not a hotel. It’s one of the most splendid and architecturally “perfect” religious buildings in the city with gorgeous stained glass windows.
Check out the Institute of the Arab World both for the building and the museum. You may want to take a stroll along the canal St Martin on the eastern side of the city. The area has become popular in the last 5 years & has lots of life.
Anywhere you walk in Paris, keep your eyes open for interesting details on buildings – there are all kinds of sculptural and various architectural gems on numerous buildings that otherwise aren’t designated as anything special.