I just visited the Mullin Automotive Museum in Oxnard, California. Not a photo hotspot (although they allow photography as long as you don't use a tripod), so I thought I'd mention it here. One of the world's great collections of French cars: many Bugattis, most restored, but some original or even as found in a neglected state and preserved as such, Delahayes, Talbots, even Peugeots. There's a small selection here: The Collection - Mullin Automotive Museum: Celebrating the Art Deco Movement

Limited hours, but well worth the drive.