Next week, thousands of rich car collectors from around the world will converge on a small patch of sand and grass in Northern California for a week of buying, selling, trading, gawking and driving. It's called the Concours d'Elegance—and while it began as a small auto awards show and driving tour, it has since become the car-a-palooza for the super rich, with more than $400 million worth of autos to auction off. There are also endless parties, races, displays and sponsor events.
Last year's auctions featured the most expensive car ever sold at auction— a $38 million Ferrari 250 GTO. This year will be a more modest affair, with the most expensive cars likely topping out around $20 million. But there are still likely to be some jaw-droppers—almost all of them Ferraris.
Here are the 10 cars that could be among the most expensive for the week. Estimates come from the auction companies or other car-valuation experts.
—By CNBC's Robert Frank
Posted 5 August 2015