Classic cars abandoned for decades in French barn valued at $20 million

These, of course, are no ordinary cars. They include storied brands like Bugatti, Ferrari, Maserati, Delage, Delahaye, Hispano-Suiza, Panhard-Levassor and Talbot-Lago.

The jewel in the crown is a Ferrari 250 GT California Spider with covered headlights, one of only 37 ever made, which is valued at up to €12 million ($13.7 million).

The car accounts for 13 of the 100 most expensive cars ever sold, and was found hidden beneath a pile of old car magazines.

Also in the collection is a 1956 Maserati A6G Gran Sports, with coachwork by Frua, is one of just three in the world. It is expected to sell for about $1 million.

The car was immortalized when the American actresses Shirley MacLaine and Jane Fonda were photographed in it, alongside Delon. Historians, however, thought it had become lost forever.

“A collection like this can’t fail to arouse the passions of those who love automobiles, as well as art and history enthusiasts,” said Lamoure.

“Never again, anywhere in the world, will such a treasure be unearthed.”

CNN