A dream car collection now covered in dust has apparently been hidden in a barn in western France for at least half a century.

Roger Baillon, a French transportation entrepreneur who badly needed money in the 1970s, had to sell around 50 models from his classic car collection, but some of his treasures stayed in the French barn until they were discovered by the Collectors' Car Department at Artcurial Motorcars.

Around 60 cars in varying degrees of disrepair were found "under makeshift corrugated iron shelters and in various outbuildings," according to an Artcurial press release.

Baillon, a long-time car enthusiast, had ambitions to preserve the history of pre-war vehicles in a museum, but his business suffered losses before he could realize his dream of restoring the car collection.

"What is so special here is the number of cars, the range (from the early days of the motor car to the 1970s) and the quality and pedigree of the models," Pierre Novikoff, senior specialist at Artcurial Motorcars, said in a statement. "It's a discovery."

Novikoff unearthed the collection along with fellow "treasure hunter" Matthieu Lamoure; the two researchers got a phone tip about possible rare cars at a property and investigated.

"The cars weren't stored in solid, purpose-built sheds, but completely makeshift constructions," Novikioff described their find. "We came closer and realized that there were dozens of cars parked underneath. We soon realized that some of these had been put there 50 years earlier and left untouched."

The rediscovered treasures will be up for auction on Feb. 6 in Paris. Despite the damage from over the years, the collection is valued at some $18 million thanks to highlights like a a 1961 Ferrari 250 GT SWB California Spyder.

"All the cars are significant for their heritage, and we hope that some of them will join big collections in and outside France. Perhaps even museums," Lamoure said.

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