The towers and ramparts of Aigues Mortes - well worth a visit for the view over salt pans in one direction and pretty canals in the other. In summer this place sweats. Find Restaurant le Minos on Place Saint Louis and order their rouille - it's superb.
I've been in front of it, have been driven around it but I've yet to climb the 284 stairs to the top of the Arc de Triomphe. I hear the views are spectacular.
The Chateau d'If off the coast of Marseilles, immortalised by Alexandre Dumas's classic novel, The Count of Monte Cristo. (image from www.freemages.co.uk)
Carnac is a megalithic site filled with row upon row of mammoth upright stones or menhirs, just like the one Obelix carries around in the Asterix books. What they were for is anyone's guess. Fascinating to visit, although not easy to get up close and personal with the rocks unless you take an organised tour as most are now fenced off.
Les Eyzies de Tayac - a picturesque town in the Dordogne region, with calm canoing on the adjacent river and troglodyte dwellings in the cliffs above the main street.
The Abbaye de Montmajour, not far from Arles. This place has a seriously spooky vibe and I was happy to get out of there.
The Abbey of Mont Saint Michel. In spite of omnipresent tourist hordes and a climb to the Abbey that will have you huffing and puffing, the visit is well worth the trouble. Just be careful not to leave the car in a tidal car park! (Image from parisvision.com)
La Cathedrale de Notre Dame de Paris. Iconic, with or without resident hunchback. Image courtesy of amazing site called greatbuildings.com