A Seine river cruise is one of the easiest ways to see Paris's major landmarks from the water without walking: Notre-Dame, the Louvre, the Musée d'Orsay, and the Eiffel Tower all pass by in about an hour. Several companies compete on the Seine, with different offers and departure points; "Bateaux-Mouches" has become the best-known name to the general public, but it's only one of several operators on the river.
The main operators
Bateaux-Mouches (dock at Pont de l'Alma), Bateaux Parisiens (Eiffel Tower and Notre-Dame), and Vedettes du Pont Neuf (in the middle of Île de la Cité) are the three historic operators; each has its own prices and schedule — check their official site before booking.
The classic sightseeing cruise
A roughly one-hour loop, no stops, narrated in several languages, passing most of the major landmarks along the Seine within Paris.
Meal cruises
Lunch or dinner on board, at a noticeably higher price than a plain sightseeing cruise; book ahead, especially for evening dinner cruises.
Tips
MEILLEUR MOMENT: Late afternoon or early evening gives the best light on the monuments, and after dark, the illuminated landmarks (Eiffel Tower, Notre-Dame, Louvre) are especially worth it.