I would recommend visiting the Sacré-Coeur Basilica and surrounding Montmartre neighborhood. The church itself is really beautiful and sits atop a hill overlooking the city (hence there are great views). If you are a fan of the film Amelie you will DEFINITELY want to go here. Many of the scenes were filmed in the Montmartre area. There are a lot of little cafes and bistros and a lot of artists hang out there. It's really fun to just grab an espresso and wander around watching them work.

Have fun!