A spectacular 75-year-old concept car described as the "world's rarest Aston Martin", the Atom, will headline Bonhams' Goodwood Festival of Speed Sale on June 27 in the UK.
One of the earliest fully running concept cars known, the 1940 Atom is hugely significant to the long-standing British marque.
The car was finished and registered just weeks after the Dunkirk evacuation in 1940, with the second world war well underway.
At a time when all metal and fuel was contributed to the war effort, the Atom was one of less than 750 private cars newly registered in the UK in 1940.
The vehicle was built and designed under Aston Martin owner Gordon Sutherland.
A one-off, it was designed to be the smallest and lightest saloon possible, yet retains the performance of a contemporary sports car and the comfort of a saloon body.
Capable of 90-100 mph, the car was used by Sutherland and his wife throughout the war, but was often stored in his factory for months at a time, as fuel was hard to come by.
Nonetheless, Sutherland racked up 100,000 test miles with the knowledge that the Atom's technological innovations would be incorporated into future Aston Martins when production resumed following the war.
When industrialist David Brown tested the car, he was so impressed he bought the company in its entirety, with many of the Atom's groundbreaking advancements incorporated into the much-coveted DB series.
Among the landmark features are: a fully lightweight yet rigid body with tubular spaceframce chassis structure, parallel-linkage coil-sprung independent front suspension, the first UK use of the "almost universal" Salisbury back axle, and the first use of Aston Martin's new 2-litre (DB1) engine.
Bonhams' James Knight, group motoring director, described the Atom as "plainly one of Aston Martin's absolute landmark designs, and certainly one of the most exciting one-off British cars we have ever been asked to offer.
"It is unique, it is super sophisticated, and when one considers it within the context of 1939-40, it represents a monumental achievement. That the Atom has survived in almost constant use, and is today so beautifully conserved in highly original order, is a great tribute to the enthusiasm and taste of the Aston Martin connoisseurs who have fostered it for so many years."
The car has not been given an estimate, with Bonhams stating that it is "nigh on impossible" to place a value on it. However, it could well exceed the $29.6m auction record set by Juan Manuel Fangio's Mercedes W196 at the Goodwood Festival of Speed in 2013.
Prior to the sale, Bonhams will hold its annual auction at the Aston Martin works in May, starring the DBS from The Persuaders.
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