I am arriving at CDG airport at 11 a.m., renting a car and driving to Chartres. I am considering stopping by St. Denis to see the cathedral, but I am wondering if there is secure parking very near to the cathedral. I understand this is not the best (!) neighborhood.

jal52,

Dont miss Saint Denis, is a must see in Paris.Also is one of the oldest Cathedrals and many Kings and Queens of France were buried there. I cant answer your question about the security of parking your car.When I go visit the cathedral, I always take the metro. The neighborhood is very etnics ,in a way interesting, a working class quartier, also it has a very modern Monoprix, that have a large selections of wine and cheese. Enjoy La Ville Lumiere,
Bon Voyage,
Kismet

I don't think you'll be attacked in broad daylight there/ I've been there alone, as a single woman, in the daytime sightseeing and saw nothing unusual anywhere (and I was in a lot other parts of town). It is a major tourist attraction and monument of France, and there is a Tourism Office right in front of it. I know St-Denis itself it not as ritzy as some other areas and does have a higher crime rate in some ways than other areas, but I don't think you need to worry about visiting the cathedral in the daytime.

There is lots of parking around there. The main parking garage is off rue Jean Jaures not far from the basilica (a little north of the Basilique metro stop) -- address is 4 place du Caquet, if you have a good map. I think it's under the Carrefour store.

Can anyone else advise me about parking at St. Denis? I am concerned about leaving luggage in the car trunk, not in sight.

I have never come across a secured public parking garage in France, but then I never looked for one. Take Christina's advice and make sure that your luggage is hidden in the trunk.