The 3rd Grand Prix, 12 Hours of Sebring, was the inaugural round of the first F.I.A. World Sports Car Championship and was held at the Sebring International Raceway, on 8 March 1953.
A total of 81 cars were entered for the event, across eight classes based on engine sizes, ranging from up to 750cc to over 8.0 litre. Of these 59 cars practised, 54 qualified to race.
Amongst the mostly American entrants, the greatest news for the 1953 race was that the famous English Aston Martin team would join the French factory DB’s for the 12 Hour competition. In fact, David Brown and René Bonnet, heads of these European manufacturers, both went to Florida to watch the race. Bonnet also took part in the race.
The race started at noon, and ran until midnight, on a day described as "partly cloudy and mild", in front of an estimated crowd of 12,500 spectators.
The Aston Martins made a great start, leading the first 32 laps of the Florida road course before losing the lead as a result of an accident. The #57 Cunningham CR-4 then took over lead and was never headed for the rest of the race.
The car was driven by Phil Walters and John Fitch took the winner spoils for Briggs Cunningham’s team. They were boosted to the lead when the front running Aston Martin of Geoff Duke and Peter Collins collided with a Jaguar, and was forced to retire with accident damage. Walters and Fitch, driving their Florida license plated Cunningham-Chrysler C4-R, to victory covering a distance of 908.9 miles, averaging a speed of 75.338mph. One lap adrift in second place was the Aston Martin DB3 of the Reg Parnell and George Abecassis, despite reportedly being hampered by having one of its headlamps not working.