We've had the big Michelin map of Paris and used it on all three of our trips. I LOVE the idea of photocopying the areas you plan to visit most and enlarging them. But most of all, I love that big map.

Another option if you know what places you are going to visit..

Use mappy.com..print the map of the area and also the route direction. Very easy to do and to read, then just toss them at the end of the day