Maybe you?d also like to visit the Bastille-Quarter, good for souvenirs. If you want to see nice churches, there are lots and lots. On the Ile de la Cite (center) definitely go to see the Sainte Chapelle in the Justice Palace, there?s a small chapel in blue and gold, amazing, and above that the church with those beautiful windows. Go over the bridge to the Ile St. Louis, the second little island on the Seine river, to see some nice houses 17th century. Be sure to check the Notre Dame and walk around it, at the back there?s a little park. Place de Concorde is just filled with cars, forget it, you?ll pass by anyway. A nice square is the Place de la Vendome (where you also find the Ritz). Maybe you?d also like to visit the Cathedral of Sacre Coeur, which was built up after the "Paris Commune" in 1871, as a sign of regret for the "crimes of the Communards" standing over a mass grave of killed Communards. There are stairs, and from outside it?s a nice sight, down to the old Montmatre, another market quarter of the city. The musee D?Orsay could be nice, but skip it if you have no time.. if you have more time, there?s Picasso and Rodin museums.