Everyone has their top 10 list of attractions for Paris but among the must-sees the following feature prominently:
Eiffel Tower
Amongst the most touristy places to go. Funnily enough photos taken from the top don't look like they've been taken in Paris because, of course, the Eiffel Tower isn't in them. To cut down on the queue, take the stairs to the first level and the elevator from there.
Musee du Louvre, Musee d’Orsay and Pompidou Centre
You could easily spend a week in each. If you only have a day, limit yourself to one area of the museum as otherwise you'll find yourself very blase "oh, another Matisse" after a few hours. If you can visit only one, the Louvre has the top works (David, Mona Lisa, etc.) but the Musee d'Orsay has a better range.
Notre Dame and Sainte-Chapelle
Although Notre Dame is much more famous, Sainte-Chapelle is by far the nicest of the two.
Arc de Triomphe and La Defense
Very impressive in scale. Take a LOT of care crossing the road at the Arc de Triomphe. Personally I didn't think much of La Defense but apparently it's very popular.
Jardin du Luxembourg and Bois de Boulougne
If you want a bit of peace and tranquility in Paris, these are the places to head for.
Palace of Versailles
This is a little outside Paris but easily reached on the train. Don't miss it!
Nearest airports include Charles de Gaulle (CDG) and Orly (ORY) which are served by mainstream airlines. The rail connections with the city are excellent. Beauvais (BVA) is Ryanair's Paris airport, around an hour north of the city.
High speed trains from London's Waterloo station arrive in Paris Nord.
