It is very appropriate that Paris´ World Heritage area is called "Banks of the Seine", because few cities are so defined by the river flowing through it as Paris is (none, I would say). Almost all the major sights are located on or close to the river, and there is no better way (who cares if it´s touristy and kitschy?) to enjoy Paris than by taking a river cruise in a bateau-mouche. Attractions like the Eiffel Tower (who would believe it was so unpopular to Parisians in the beginning?) and the Louvre are world-class sights in their own right anyway, but there´s so much else to see to keep you occupied for ages - Notre-Dame cathedral, the Arc de Triomphe and the Champs-Elysées (in my humble opinion the most beautiful street in the world), the Sacré-Coeur and Montmartre, to name just a few. I could be mistaken, but I believe Paris is the most visited city in the world, and it´s easy to understand why.